Our level of current ability sounds very similar.Yes, I was referring to the common fingering - PIPIPMIAMA etc. I could no doubt play it with P and I as these fingers have never been affected. However, after years of playing with just P and I, I am yearning to get more and more repertoire under my belt that uses all fingers (I have also been relearning a lot of pieces I have been playing with P and I). I am getting my money's worth from the Carcassi OP.60 studies at the moment.
M is my sluggish finger, and the rapid AMA at the top of the VL Etude 1 pattern is what slows me down in that piece. Maybe I should try it with PM to use your strategy. I try and use PM in scales when I can, I can see the logic.