Obviously what Mr. Dennett means by free will may be different from what you thought it meant. One way to tease out the difference is to realize that he leaves room in the human mind for intent—and he points out that other types of minds may lack it. Thus the distinction between “competence” and “comprehension.” Competence is the ability to carry out an act, but comprehension implies that the organism (or robot) carrying out the act has intent and an understanding of what it is doing. As I like to say, you may have a theory about your dog, but your dog doesn’t have any kind of theory about you.More to the point, it seems that what he means by the word illusion is different from what the the rest of think it means. An illusion is generally understood to be an appearance that does not accord with reality. As for intent, is that not equivalent to purpose? Are you freely intending, or is your intent also determined? Moreover, there has been research recently that suggests your dog may well have something on the order of a theory about you.
There is also the problem that no physical evidence has yet been adduced for Prof. Dawkins's beloved memes.
The bottom line is that Mr. Dennett and Mr. Gazzaniga continue to act like the rest of us, choosing potato salad instead of cole slaw, etc. Socrates would have had a field day with these people.