its all about making decisions.
how high is the starting skill? how is his potential? are you training for teambuilding / transfermarket?
---> is it worth to focus a half season on blocking, not heaving the time to train other skills? i think we all agree an ideal sf should also have decent passing, decent rebounding aso.
what role swill your sf play in your team? is he a roleplayer with limited offensive weapons but a defensive stopper? does he need a lot of rebounding or does your frontcourt gives you enough power on the boards?
i always said blocking is underrated, but again imo its all about decisionmaking. blocking can be usefull but isnt nessecary. i like to play 3-2 zone with 2 blockers on the boards. my starting-sf is a really bad shotblocker, if i could build him again, maybe i'd train it. but it works pretty fine for my team, even if in my last game my sf fouled out pretty fast for some reason. i dont think his low shotblocking-skill was the reason (he is averaging 1,9 pf over 11seasons) and the other team was purposely losing with a training-lineup