No, GTWF gave four hooks, not three. So total eight attacks in a full sequence. Just picking up two weapons gave you six attacks (but with massive minuses to hit of you didn't have TWF), ITWF gave you seven attacks in the sequence (four main-hand, three of the half-strength hooks).
Now it will instead be a percentage chance on your main hand attacks that the off-hand attack will go off "with-it", or not. For GTWF that chance is 80%, Then there are asorted bells and whistles to sort of push that up a little for the Ones Chosen By the Devs.