I think he really just had to get his rhythm going. Biden was never really a terrific public speaker even at the best of times (Or Obama was just like, absolutely world-class). He did get his promises out, though.

At the end of the day, Biden could have just twerked on stage for 100 min, and I still would have voted for him, as long as he has a plan for the next four years. He's actually gotten a shocking amount of good stuff done for the average american, though some of it, like rebuilt bridges, high tech factories and prescription caps, might be years away before we reap the full benefits.