i guess I don't know what that process is supposed to do. if they heat up the springs, bend them, then reshape them back to original dimensions and do nothing else (ie, remove a leaf) then the only thing that could be different is the strength or "springiness" of the metal (i'm sure there is a proper mechanical engineering term for this parameter - i'm an electrical engineer). For this to lower your truck the springs must become weaker, which to me seems easier to accomplish by just removing a leaf.
But we've reached the extent of my knowledge of this subject... If it were my truck i would go see a spring shop.
