Prodigal Piano Prodigy Returns?

[kickair8p]

A twelve-year-old genius pianist (not really a prodigy, sorry) described as "a fine clinical player" gives up piano (to become a scientist) and doesn't touch it again until his mid-thirties. The very first time he puts hands to keys and tries to play something (which he remembers accurately), what happens? Is it humanly possible to do it as perfectly as twenty-plus years ago, or would he fumble a bit because his hands have changed, or would he be terrible because his muscles will forget no matter what his brain remembers?

Googled every combo of piano, practice, and/or memory I could come up with, no joy.

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