I think Roguelikes are the games I play most.
Plus the occasional runs in the other "Roguelikes" like FTL, Spelunky, Issac (Still annoys me when people call em Roguelikes)
But switching between DF, Nethack, Angband, DCSS, CataDDA (Mostly those games) I personally it find quite easy.
You play em for a good while, and really, if I havn't played it in a good couple of weeks, the '?' key basically works in every game for a list of controls.
Once glance at that and I dunno, it all comes back to me. Mostly, the only thing I need to remember with them all is the Look command.
I can't even remember what it is for Angband right now.
Nethack I think is 'v'
DCSS I can't remember (Been a good while since I played that)
DF is 'l' or 'k' and then in adventure mode I'm sure it's the other key.
CataDDA is 'x' which is pretty much what I always press instinctively at first.
And then Cogmind, I think was 'x' but I'm not sure, don't get to play it much yet.
It's that particular command though which annoys me, xD Cause it's different in every roguelike. Heck it might have even been something totally new for Caves of Qud. Can't remember that one either.