Not sure this stat makes sense and it doesn't feel like it should.
Edmonton has won 34 playoff games out of 70 in McDavid's career. Pittsburgh has won 100 playoff games out of 183 in Crosby's career.
Simply more chances for Crosby's points to count towards a winning effort.
And McDavid's higher PPG means he was putting up more points meaning a lower chance for one of those to be a GWP.
That being said, winning is not some random thing attributed solely to being on a good team vs. a bad one.
Sure, how about this.
RNH - 12 GWP in 59 career points (.203%)
Bouchard - 12 GWP in 54 career points (.222%)
Draisaitl - 14 GWP in 105 career points (.133%)
Eberle - 8 GWP in 47 career points (.170%)
Schultz - 8 GWP in 42 career points (.190)
Hyman - 8 GWP in 58 career points (.138)
Evander Kane - 7 GWP in 43 career points (.163)
Barrie - 5 GWP in 21 career points (.239)
Ekholm - 8 GWP in 50 career points (.160)