i took a look at kimiko's strokes and see why she plays with a heavy racquet. she is a definite pusher. she doesn't have any loop at all on the forehand. the stroke starts from the ground with a short up stroke/push. pretty much her racquet does all the work for her. seems to work just fine for her.
(3)Volkl PB 10 Mid 375gm 360sw 12gm@3&9 10gm@handle 9pt HL, 1HBH 3.5ntrp