I know this is a random aside.
One of the reasons Tatum is shooting worse on 3s than you'd expect given his shooting ability is that he takes a lot unassisted ones (the step backs and other off the dribble 3s). Those are naturally worse shots than catch and shoot 3s, but they're essential to opening up the court for the offense overall and to give Tatum better driving lanes.
Its baked into the design of the Celtics offense to have Kemba/Tatum/Marcus three of our lead ball handlers taking these shots. I wouldn't be surprised if they wanted Gordon to take them too, but he isn't as comfortable preferring to drive into the paint most of the time. (which is working great so I have no complaints)
Celtics coaching staff occasionally talked about how they wanted Kyrie to take more threes than he did in Boston, they have had this concept pretty much since IT4 was our lead guard.