Right now, Hanigan does 3 things for the club:
1 - He is allowing both Leon and Vazquez to catch 4/6 or 5/7 times a week. If Vazquez were up, either he or Leon gets the 2. Vazquez needs to play every day to work on his hitting, and the way Leon is going right now, that would change in Boston.
2 - He catches Porcello and for whatever reason, that combo is working. And as Crash Davis said, "If you believe you're playing well because you're getting laid, or because you're not getting laid, or because you wear women's underwear, then you *are*!"
3 - He attempts to catch Wright, which has to be like trying to catch a double header and so it keeps Leon fresher.
Put whatever value you want on any of them. The first has a lot of value IMO. My guess is come September, Vazquez comes back up and Hanigan will be reduced to catching only Porcello (unless that magic ends).