you can but it's hard. This is how i got my shifts smoothed out...

bascially your heal floats back and forth an inch or so against the carpet while your toes are rolling the clutch (if you want the pedal to touch the floor). It is easier to roll out then in... I took a ton of practice but my shifts are smooth. I am just glad the clutch is not to tight, it would just make things worse.

oh yeah - when doing fast shifts i stomp on the clutch and the gas