A recent performance of a familiar Mozart Piano Sonata proved [insofar as an ephemeral moment in a one-time occurrence can "prove" anything] central to my observations about the effect on players of the music we play.
The performer was doing splendidly in terms of technique and memorization. As I listened I was increasingly aware of the bizarre twists that comprise the sonata's theme. The pianist must have noted these twists as I did because at the next repetition of the material he got stuck. I would bet that the performance was prepared by stressing repetition as a reliable source of structural orientation, while more emphasis on the variability of the material -- the several ways it could be heard -- might have engaged the mind in a different enterprise which would have made getting stuck less likely.
Nothing serious. Just something to think about.