Hand Tools Archive
I know fairly little about DE razors (I have had a 1904 gillette or something of that sort - too primitive, and still have a gillette fat boy and superspeed - i use them once in a great while when traveling).
I've got a gaggle of feather razors, but they're the single-edged kamisori style (got them for a song). I'm embarrassed to admit I've never tried them.
Those blades are intentionally flimsy (all of them, all DE blades that I've seen - to work in different razor designs) and I would guess that the longevity in the feather DE razor (which I've never seen in person) is probably a testament to the razor itself holding the blade more firmly and not allowing it to slap and take hairs on for cutting at anything else other than an ideal angle.
How's that for a guess!!
I worked to get faster with a straight razor early on and that sort of ended my fascination with DEs, but far preferable to buying plastic junk for a landfill nonetheless. I can't seem to get anything else to shave without razorburn, but it seems that in the world of shaving, everyone perceives just about everything different (not making any statement about one way being better than another - they can both be expensive to experiment with, too).
If I know anything from interviews of old japanese razor makers (translated), I recall that they love the idea of taking an established design and then making the attributes of it better so that they can declare it better. I see this excerpt on one of the feather DE listings
>....ultra premium shaving tool, with exacting tolerances....<
It reminds me of tanifuji and some of the other straight razor makers of the time -rather than matching german razors, they pretty much attempted to make them a little bit better in every way that they could figure out (tanifuji's razors are exceptional - not saying that in a spec sheet audiophile kind of way that they're great because tanifuji said so, but they're great because they seem to be very easy to sharpen and keep sharp and they're tolerant of just about anything, and finished uniquely well.
I don't know if you could find out exactly what they did to make them work that well, but if you could get a hold of someone at the company that spoke english, they might tell you (and might not). I'd bet it's intentional and the result of experimentation and little improvements.