Now there's a "blast from the past" that usually doesn't get much discussion here (and also apparently didn't sell many drives)...   I've seen several threads here that describe the "memory tricks" used to store sector data for R/W. And those remind me of another one -- the TRAK with its track buffer. (I had an AT-D2 that worked, and think I still have the board from one.) IIRC, it had a 2K memory module for the track buffer. No problem in SD, but on the surface, it is a bit shy of enough