Roy may not be good at pushing the tempo, but Portland's offense was quite efficient with him running the show this season. They were, as I recall, #2 in efficiency. Offense isn't why Portland didn't make the Finals, IMO, defense is. When you also factor in that Oden, Bayless, Rudy, Batum and Aldridge are likely to improve (at least as a group), I wouldn't worry much about the offense.
My worry would be about whether the defense is going to improve. I think Bayless actually has three big effects there:
1. He has both the tools (other than a large wingspan) and the mindset to be a good defender. Lots of players have the tools, but many don't have the desire to play defense. From all accounts and from observation, Bayless puts a lot of effort into his defense. He wasn't a great defender this season, but he was a 20 year old rookie playing sporadic minutes. I think he's likely to be a major improvement on the defense of Portland point guards of recent vintage.
2. Bayless, as a someone who can be an on-the-ball play-maker, will take some touches and pressure off Roy. Roy won't have to expend as much energy being the sole play-maker, which will hopefully allow him to put more energy into active defense.
3. Less penetration by opposing point guards means less fouls by the big men. The fouls mean points for the other team and they mean more bench time for Portland's big men, especially Oden. Oden being on the bench is not a positive development for the defense.
Ultimately, then, I think Bayless can do a lot to push Portland toward title contention. I think he can function as a dangerous component in what is already a highly efficient Roy-led offense and he can make a defensive contribution that could have several positive impacts.
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