My default is giving the comm to the tank in order to encourage them to continue tanking. When I first began tanking it was stressful and for whatever reason I end up with jerk BRDs who pull everything and berate me for not tanking better. So going off that, I assume most tanks have met some toxic players during their runs so a comm their way would make their day. The only times I don’t comm the tank is if they were the ones being toxic.