Actually, one of the interesting things with squatting on knowledge is when I got into this hobby (late 2005 or early 2006, I can't remember), there were a lot of people who had done not very spectacular things as pros but they sort of believed everything they knew had to be kept secret, and making money off of what they wanted to demonstrate was right around the corner.
By that, I mean a lot of those folks would show something they made, and then when asked about it, say "that's a secret that I'm not telling" for very unspectacular stuff.
I have made 10 guitars, but all are solid body - they weren't that thrilling to make, but the key is I've bought a boatload of guitars and if you're going to have guitars around more than what you play on a daily basis, flat top guitars aren't it. They are alive "fo eva" and the one you last played that was great that's got scalloped bracing put aside for a year or so will not be the same guitar when you get it out of the case. BTDT. Relatively little happens with solid bodies, and they can be more fundamentally different in shape and kind of qualities. https://i.imgur.com/v5fpTAr.jpg You can take oddball stuff like scrap flasawn maple and make a one off neck (no power tools in this case at all, but for the tuning machine holes here - not even for thicknessing the wood or the walnut strips, all done by hand.
That's amateur stuff- amateurs can afford to spend time doing that, really staring at the work for a while, thinking about it, making it - maybe making the guitar over a month instead of in three days.
I've gradually switched to tools, but when I wanted to learn more about heat treating (to the right of the guitar here):
https://i.imgur.com/1ldQpGI.jpg
https://i.imgur.com/g4t36uU.jpg
...I encountered a guy who was selling knives and he at least claimed that he was bettering peters' heat treatment for a relatively popular steel. He probably was. He wanted to talk a lot about it, how good his knives were, how thin he could make them and so on and he wanted only to talk about the beginning of the process and not suggest what he was doing. I sort of get that - there's a little more nuance than how he makes a wood filler that nobody can see, or howhe may have made to work on a slider to pound out substrate for veneering. But it still seemed dorky. There's opportunity for a good knife maker just in effort that's more valuable than "secrets" - the secret is that if you work at the top level, people will buy your stuff, they will buy more and talk about it and they probably won't care that much about your process.
Remember, I'm an amateur.
About three or four years ago, I sent samples of the steel in the chisels above in test coupons to a metallurgist. They tested better than anything out of a furnace schedule. I've learned a lot since then -what steels will do that (carbon >1%) and where you'll just match book if you do well by hand (O1, for example, or other steels 1% carbon or less for the most part). Metallurgists aren't really into amateurs doing work by hand, so the metallurgist wasn't that pleased to see the results, but at least he didn't lie about them and change the numbers. He was hoping to prove to me that what I sent couldn't be done, and then just changed his tune to it can't be done consistently (it can, at least in a small universe of steels).
I don't really have any secrets. I thought about it after developing a process - what if I make chisels in retirement, and so on. It seemed pointless pretty quickly. The people really making money aren't making stuff - they're building a following, making a little bit and then selling out and having most of their work done by contract and then entirely manufactured with just their brand on it.
On the bottom end of the guitar market, the factory made stuff in indonesia has crept up to a point that it never was remotely close to 30 years ago and you can get a boomer of a guitar made out of decent wood - talking about acoustic - for $500 on sale somewhere because the brand isn't popular here in the states and someone is giving it a shot, anyway. The market has gone dumb and growth in sales is stuff like fender or gibson relic work that isn't made of the same stuff in the same way it as made before - the wood is from fiji, for example, or the pickup parts from china not made the same way. The guys who really were chasing quality as individual makers making guitars by hand have kind of lost the educated customer base to limited collectible manufactured stuff where instead of being a CFO with a 25,000 archtop guitar that feels and sounds like something God may have dropped when he passed in front of Moses, it's ten CFOs celebrating that they have each spent $25,000 for a $5000 guitar, but there are ten, so they have someone to stand next to when they measure as opposed to having to explain what they have to everyone all the time. Plus, maybe the manufacturer spent $1000 putting paint on such guitars in a way that they look sort of like something a boyhood hero played in film.
There have been a few true masters who have floated through the forums - kind of like the elite guitars, they don't really sell as well as a guy who tells you that you can make boiled linseed oil by buying something in a can and putting it on a grill.
We do have our share of people whose biggest secret is also what they do and don't do. Googlers who have attempted to have woodworking businesses, but filed for bankruptcy and in between, failed to hold other employment that really is their primary skill, returning to imply that they really know what it takes to "get to work" - barking at amateurs and other professionals alike. We have no idea what they're so jealous of, or why they don't notice that few bark back at them because of indifference. Perhaps solvency, or perhaps it's a dog from a bad blood line kind of thing - such dogs bark and growl no matter what, offer nothing to to pack, and really don't have a point. Maybe those dogs that run up to the fence and bark and growl but who don't even have the skill to fetch the morning paper for their owners really are barking just for attention and can't get it any other way.
Maurice, you remind me more of my good friend George. George learned design formally, but learned most of what he has done making by making. He did world class work by day, and then did it at night. he's unafraid to say he's a good maker, but also has no secrets if people will listen. He has no secrets because he's first not worried that you're going to steal his work, and second, well aware that when he does really high level work, probably nobody would be able to in the first place. I don't know if it's so much that kind of endless ability to find heirs or well-off folks who will pay shop rate for really unique fine work, but George is nuts about the work. He's not nuts about the recognition - he is bonkers about fine work and the satisfaction of pushing and doing more of it. There is but one quick way to really piss him off - ask him for information at length, imply that you're going to use it, and then go and find someone like a magazine writer and say "there was an article in finewoodworking that said __________". That is, make him go to some effort to organize things for you and then show him that you wasted his time and effort.
He also referred to the journalistic published makers, at least some as "the best I can tell, if they make something, they write a book about it", which is more of a slight than most may imagine. It's a shot - a real maker makes. A person primarily seeking to publish makes something, and then spends a great deal of time writing books because they probably couldn't avoid bankruptcy courts if they were just making.
Whatever niche stuff I find out with hands in the forge or hands on tongs or snapping metal samples, it's not that difficult. It's certainly more valuable and more practical than taking 14 classes and buying more equipment, and whatever you come up with, you own. When you read what someone else does and you just copy them, you're borrowing it. The knowledge has little as far as roots go and if you forget it and misplace your notes, you've lost it because most of your nerve endings were holding back anyway while you thought about copying the steps someone else did vs. being three dimensionally involved in what you're doing and setting the roots so the knowledge can be fertilized and grown further later and tied to other things. The folks who are really nuts as makers have a lot of roots - you can tell the difference when you talk to them, and the issue isn't so much that you want to learn to copy everything they do - it's to spot the difference between them and the googlers who bounce from one failure to the next but have ire for everyone along the way, offering opinions and implying authority and going to great length to hide the googling and failing that drives the desire to practice online escapism.
Back to the niche stuff - everything good that I've found "in the dirt" by using the shovel rather than reading about excavators is published somewhere. I use that as a means to see if what I find is well known - it generally always is. You do it, it works, someone did it before and at this point with information everywhere, probably published it. You quench steel once before refining grain and find that the grain refinement is more effective after the quench? You can find out why. But if you are the googler-failure type instead of someone looking to set roots, you'll never find that information, anyway. Googler-failures will tell you about how much they've been exposed to, how well read they are - you'll have a near impossible time finding any of their portfolio, but you may find some answers that they wish to hide.
We're transitioning at this point really from the folks who want to keep their secrets - not telling anyone that you can quench steel twice and get better results than if you do it once, and what you have to do before the first one and in between that and the other.....now that information like that can be found, even if it takes a little more work, most of the people who want the secrets or think they do find looking further into them to be too much work, anyway. Things done by hand in heat treatment, for example, by knife makers common in the 90s are now considered to be irrelevant, because they are not valuable. You can't charge for them, and they are effortful. Much like a jig, the "secret" is now to buy the right equipment, which does work just like a joinery jig might, but offers the buyer the ability to stop testing themselves and settle for commodity results, so they can go back and get on to what they really want to do - watch netflix or read magazines.
Added later 03 min 33 s:
To your original point, there are definitely people who have set up online publishing or youtube or whatever that want to tell you heat treatment, something in my case that I wanted to figure out on my own after not finding much success with other peoples' advice. A maker can observe results and compare them. Influencers will show you how to do something, poorly - the result isn't the point - the payment for the influence is.
Nothing that I can think of that's valuable in making a better chisel has come from an influencer. Which does suck if you know that from the outset. breaking steel in half, taking pictures of it and buying a hardness tester to confirm something that's not easy to do just by biting or licking - it's the secret in the dirt ben hogan talked about with golf. There's no secret in the dirt - the dirt is what you to get better so that you're smart enough to know there's no secret. Most people will lose interest when they find out that doing rather than reading or "knowing" without doing is a lot more effective.