Not be critical, but two questions come to mind.
One, we generally torque bolts well lubricated. Over time the
oil goes away. Loosening and re-torquing (if that is a word) may eventually end up with a dry bolt, resulting in less stretch in the bolt. Don't you risk making matters worse?
Two, each time a bolt is loosen and tightened, it is unstreched and then stretched again. A bolt is only good for so many cycles, especially a head bolt.
However if you have less problems by doing this, who am I to argue against good results, but it does seem questionable to me, at least in theory.