I do not buy it. Why would GWB wear a wire on an issue he is supposedly strongest on? If he wanted to he would have worn it on either side of his heap. I think the evidence at best is a stretch.
Primarily because he is a horrible public speaker, even sometimes with a written speech in front of him, and appears to have gotten worse in the past four years. The stress of spending all that time in Crawford has gotten to him. Until the debates, all of his public appearances and press conferences were scripted and very limited. He was actually better versus Ann Richards ( though not better than Ann Richards) so the drugs and alcohol probably started catching up to him.
I do not buy it either. Perhaps, if GWB had given a better performance, I might consider the possibility. BTW, my guess is that his handlers crimped his shirt in the back, so as to make the shirt look better in the front. It is a trick that is done in clothing catalog shots with models to make every shirt look like a perfect fit.
Mine is that it's some sort of bullet proof vest. I'm sure he's recieved the threats that warrant it. And I'm sure that people would try and hit him with a car like that whack job tried with Katherine Harris. It's a vest.