Thanks, Albert. I'm sure that's true, and I remember a few of those discussions. But Ted Gioia's argument is more than just "cool jazz." He writes of Bix as the progenitor of "cool" period.
I'm no musician or music critic, so I always worry about having an opinion on things like this, but I wonder if it is necessary for Bix to have played what specifically came to be known as cool jazz for him to be an important precursor to the music.