Those Flickets were really a great idea, in their day. Some of my friends and I used them way back when. We would also try to polish the action up with anything from a paste made of Comet cleaner and water to just toothpaste. We all had varing degrees of sucess. The trouble with all those abrasives was that what we really managed to do was wear out the action quicker than necessary. Oh well, live and learn.
On the idea of drilling and tapping a blade for a stud. Even a softish blade (55RC) or so is really hard to drill, and even harder to tap. I work in a machine shop and have tried upon occasion to drill and tap hardened parts. It is possible, but in the small size that would be needed for a thumb stud, most likely there would be no success. There are other methods, ie. wire EDM and that sort of thing. Machine time is costly, and when all is said and done, it would have been cheaper to get a knife with the stud. Thus the inventor of the Flicket must have known in that time line.