Queen's Gambit Accepted Nc3 VS Nd2 Usually I play somewhere around move 5-Nc3 but I might start playing Nd2 more instead to get a different dynamic in the game. 

Is this advised? Does this have dire consequences in QGA?
Unless you have a good reason, why would you block your own queen bishop and release tension on the important d5 square?

The idea of the gambit is to intensify pressure on the d5 square. Volunteering yourself away by Nd2 is unusual.