I picked up an old Gillette Tech from a antique shop. I think I paid maybe $10 for it. Anyway It had a little oxidation, I managed to clean it up with Brasso and it looks pretty much new. I wanted to try it out but I didn't want to use a new blade because it would not be an accurate situation. I took the Derby Blade from my Edwin Jagger DE89L and put it in my Tech. It was pulling and tugging on my face like hell (prickly blade). So I replaced it with a new Astra, no more tugging shaved really nice.
So as a test I put the old Derby back into my EJ and tried it on the other side of my face, no pain, no prickly, no tugging???
So I guess my question is why would the same old blade perform any different in one shaver over the other. One thing I'll say is that I almost never get that prickly feeling with my EJ that you guys talk about when your blade get's old. I've used a blade before for months!!
Gillette Tech v.s. DE89L on "old blades"