The whole idea of trading Paul Pierce, particularly for another short window, "win now" piece like Pau gives me a headache. Really, I just can't wrap my head around it.
There are just too many variable, the least of which being whether or not Pierce is the heart and soul of this team (maybe its KG, maybe its Rondo...but it may just be Pierce), and taking him away could take away the heart which has helped them be as good as they are the last few years, and continue to rise, every time people count them for dead.
I am not saying I wouldn't do the deal, and I am not saying I would. I just would rather not have to deal with the emotional and mental anguish of this debate, unless it were more solidly on the horizon (or, in fact, a done deal). But that's just me.