Late to the party on this post....
I have '22 R1250GS which has had an abrupt & clunky quick shifter since I bought the bike, particularly from 1st to 3rd as well. Upshifts were mostly decent (3rd and up), downshifts consistently poor, even with closed throttle.
This week, I reset the transmission using the GS-911. I followed a video I found on HexCodes Facebook page to recalibrate after reset by going through the gears at idle while on center stand leaving it in each gear until the gear indicator on TFT stopped flashing.
Went for a ride yesterday and happy to report the reset made a WORLD OF DIFFERENCE in the operation of the quick shifter. Even 1st to 2nd is improved under light to moderate acceleration. Downshifting now works well on closed throttle on level ground. Downshifting on downhills while the trans is 'loaded' is still kind of hit or miss with smoothness.
Overall, YES, performing transmission calibration for me has made a huge improvement in my Shift Assist Pro / Quick Shifter