Using 11.4 oz LMRAds for 2 years, then Dunlop200's around mid 12's strung, now using 10.2 oz 500's that might weigh 10.7 strung.
Most of my peers at 4.0 don't hit hard. I can crush balls with either light or heavy rackets.
Against the occasional hard ball, what sense is fighting fire with fire? Why not add some spin, some placement, some off pace, to fight against hard hitters? After all, the hard hitters aren't 5.5's, are they? And if they are, what do I care? I"m a 4.0.
But against weak mishits, for me, a lightweight racket is much easier to put away the ball with a clean winner.