You want to claim that possession-style forwards thrive in the playoffs when one of the best possession players of all-time was also one of the worst star forwards for production drop off from regular season to playoffs of all time? 6'4" Thornton never got it done in the playoffs and 6'0" Couture and 5'10" Pavelski put up elite playoff performances for us. You can't possibly have been a Sharks fan for the last fifteen years and still believe that big guys get it done in the playoffs and small guys can't.
Besides, this post reads like you've never seen either of these players play. Martone is far more of an opportunistic rush player than Hagens is and Hagens is better at cycling than Martone. Again, you just looked at their heights and said "small player rush big player cycle". Martone plays a very specific role on a team, which is playmaking wing. He doesn't use his size very effectively or play half as physical as he should based on his body-type. He doesn't drive play and can't be the best player on his line. Hagens does and can.
I understand that Hagens isn't a great fit for the Sharks. I understand that Martone is big and people like big players. But I can't abide you just making stuff up about them because you think big player good, small player bad.
"The more unique risk for players like Hagens is they aren't good enough to play their role on a contending team and that's far more difficult to fix."
^This is just word soup. There is a greater risk that Martone fully busts or turns into a bottom-6 grinder than that Hagens isn't good enough to be a 2C.