TomD
"Hard for a newbe to imagine getting everything out, flat, parallel, etc. with a chisel and some rasps, if that's how he does it."

I don't think he uses rasps. Chisels, saw, drill, so forth.

" I mean , I read about people going to the lengths of using graphite or ink to check where things touch, etc. to get parts together properly."

Yeah he does that but it comes after he gets the blade in. I like dry erase marker

" Even with a really good eye, I can't imagine it. I'm not doubting it -- just amazed."

He does use layout (actually that may not be in the video, so a few more moments there, and he spots the blade in, but one of the things that makes a plane faster to cut in is that rather than following the ink, you imagine what it is telling you and you go for that shape. In spotting in the idea is to find the high points with ink, and then remove them and test again to get a perfect surface. Appropriate when doing an action on a best shotgun where the parts were initially CNC cut to + tolerances, or when getting points on a tool way. But with wood, while using cutting tools you need to do a somewhat bold cut. Let's say you had a plane that would cut 4 tens. How efficient do you figure it might be cutting 1 ten? Obviously not very. The solution is to cut to what you think the final line will be with enough of a chip that you have control. So one reads the spots as an indication of what the final resting place will be. The longer one can do that without resorting to chasing individual spots down, the faster the job goes, and if you are a real master, the better the final surface will be if it comes from the chisel.

This is a pretty general woodworking principle, when chopping dovetails, if one wanted to cope them for whatever reason (cut waste out with a coping saw), and leave enough to finish with a chisel, then it seems better to me to leave enough there to make for a solid cut than too little. Too much and the coping is a waste of time. Same thing on a bowl, I start cutting what I hope will be the final shape with confident cuts. I swing that shape even if I am cutting air most of the time, I don't let the initial surface dictate my sweep (well I do for safety sake if the block has dangerous or off weight lumps on it, but generally). I do not try to make very light cuts to lower high points that are next to low points. Visualize the final shape, and cut to it. When learning one has to count on a plan B, so maybe a beginner ends up doing a little more shear scraping of the final surface until they get the skill to cut all the way down with full gouge cuts. Same thing with an axe, you want to hew a beam you need to take enough of a cut to not bounce the axe out of the cut, but not so much it sticks.

It is like driving down the road. If a person had never driven it would sound like magic to say that drivers do not pay direct attention to the lines, they sorta look off into the distance. Magic right? But everyone learns that the lines are not good to look at because they are what the car wants to be between, not what it should be aimed at. Even when shooting a rifle there is the line of sight, the line of the bore to target, and the trajectory of the bullet, and they are a lot more than theoretically present if one does something like cant the rifle or pistol. In golf, I have been playing for 16 years and still can't get a consistent based on fundamentals answer about these kinds of issues. It gets complicated, but can be interesting trying to figure out what is going on. People sometimes wonder what the heck I am doing when they are talking to me, because I may have lost anything approaching eye contact. I'm off lining up objects in the environment with my eyes. Can't help it.