Quote Originally Posted by Easy_Lee View Post
The trouble with lots of smaller attacks is that TWF only gets one more attack than a great weapon, and that only some of the time due to GWM. The number of attacks equals that of PM, and PM can benefit from either Dueling or GWF to increase its damage.

In short, TWF only has that advantage in a featless game. And in that case, the smaller damage die means critical hits are considerably less impressive.
Yup, and Damage Overflow is just a side effect of triggering that bonus action from GWM you might waste some damage, but you gain a big bonus attack. Bigger than TWF and the PM bonus attack you likely would have been getting anyway.