Never gave it much thought until it was brought up here. Seems to make
sense to let the boot settle into place by leaving it unclamped, but
what about keeping out dust and road grit? That stuff can do a fine
job of grinding away at the joints. So is it better to clamp it and
risk a prematurely cracked boot or save the boot by keeping it
unclamped and risk getting abrasive grit sneaking in?

My guess is that it would be better to clamp it and keep an eye on the boots.

Cheers,

Keith