I did not see practices. I went on reports from the papers that cover the Raiders. They were BRUTAL on DHB last year....and deservedly so. This year, he is a completely different player, as stated.
1st, the obvious...he is BIGGER than last year. He has gained approx. 25lbs of muscle that you can clearly see.
2ndly, you can tell he worked hard with the Raiders WR coach, Sanjay Lal, because he runs better, crisper routes. He had a horrible time getting off the line of scrimmage last year. He has also improved DRASTICALLY, the good ole desease of the "droppsies". He dropped very few balls in both practices(from what I read) and even less in the preseseason games(from what I saw). During the preseason games this year, when the 1st WR unit would come out...they had him stay with the 2nd and 3rd unit to get the extra work.
Finally, his confidence is through the roof. Not an arrogant confidence, but a confidence that he KNOWS he can play this game and play it well at this level.