I wonder about Pres. Bush's comments about Clinton occasionally, but I really think he is just being civil and polite.
When he ignores all the horrid comments and insults levied against him on a daily basis, it shows what a gentleman he is - the ability to rise above that sort of thing is something I wish I could cultivate myself.
I think it is just a little typical genial joking about the BClinton thing. He's certainly aware that his father has made some semi-senile remarks about BC, and I think his allusion to his 'brother' and he turning sixty was hilarious.
Bush is just a person of amazing good will, annoying to those of us to aren't.
Could it be that it's not a "gush," just a clever trivialization of the Far Left's idol(s).