Should Federer switch to full-poly set? Given that his major problem nowaday is no longer trading backhand topspin, but rather when he attack them with the inside-out forehand with full force... I recall some TV stats showed he missed nearly 2/3 when he tried that. I test-switched to a few softer full-poly sets (Big Ace, Polyfibre TCS etc) from my regular poly/syn or gut/poly with some good results on these shots against the lefty dirt-baller types that I used to have problem with. BTW, I did also tried to switch to mid+ frames like Dunlop AG 200G 16x19 for 2 months+, but did not yield good results: 1. Fly way too many balls compared with the mids with the same strokes (despite higher string tension). 2. The sweetspot for mid+ frame is higher than mids (which is lower according to Wilson's graphic depiction), which I just can't seems to get used to. 3. Anything thicker than 18-19mm beam just feel so different (a little more bulky? but maybe it's just me) Again, maybe it's just me, but the string switch alone seems to help more than other things.