Tips for using 612 F1 transmission

In playing with the transmission on my second drive out, I really struggle to get upshifts as smooth as I want (and can manage in a manual). The Ferrari manual suggests flat shifts at high revs, but these are still fairly clunky. Any tips or suggestions on how best to work it. Strangely, comign off the throttle slightly on upshifts seems to help it match revs although the manual says not to do this.