The need for a front derailleur adjustment is only an indication that the chainrings have moved in relation to the front derailleur. If the drive side crank is removed and replaced and soon after, the front derailleur needs adjustment, the crank is moving further in each time you tighten it. That's what would happen if the soft crankarm flats are enlarged. If this doesn't happen when the drive side crank is removed and replaced many times, it is an indication that the perceived problem is nothing but a myth. No conjecture there, just proof.