I think there was a slight miscalculation on the part of Biden's team though. His voice was in "shout-mode" for so long at the beginning of the speech (the first 15-20 minutes I'd say) that I think he drove himself kind of hoarse. I never saw him go for a drink of water, probably because he wanted to avoid the Marco Rubio or Donald Trump viral moment. He started coughing about half way in and the section where he was talking about policy was a bit uneven. He pulled it together for a strong finish at the end and people will remember the start and finish much more than the middle.