I would assume that the "best" method depends on how much "drift" will occur over time (that is, how much the pot may move it's position due to the robot moving, shaking, vibrating, and jolting due to crashes).
The idea of mounting the pot in an easy to reach place makes adjustments pretty easy.
I've also read about replacing the pot with resistors (though I have never tried it myself), and would think that this approach eliminates any "wandering".
I don't think the "cut out the pot" works since the servo circuit needs the resistance that the pot creates as a comparison.
I haven't seen any articles comparing the merits of each modification technique, but seems like it would make for interesting reading!!! Maybe I'll be a few servos one day, do some testing, and write an article for SOR!