Yes.
BUT that doesn't mean that .30 is the most benefit he could have realized, because it assumes that his 9.58 was done both with chemical aid, AND while at peak training response.
As Bolt is known for being lazy, the absolute level of his fitness in his 9.58 should be questioned. IMO it was doped, but there is the possibility that he could have been better trained, and realized even greater benefit than he did, and produced a sub-9.58 time.
I still think that Bolt is a normally-fit 9.9x-high guy, and a very-fit 9.7x guy, clean. Likely one of the fastest-ever clean 100m guys. Let's say 9.78, that would give him a .20 benefit.
Do I think that's realistic? At that level, yes. The ".50" advantage that many have enjoyed in recent years has been documented on this board, but those were athletes who were not among the very best of all-time in their respective events.
Either that, or he is a 10.1x normally-trained guy, and 9.9x-high well-trained, and he has enjoyed a .40 advantage. It's difficult to conceive of him in that capacity, because he has put on muscularity that is cleanly believable--he filled out as a man, there is nothing out of the ordinary there. That body--the shape of which I don't think was really affected too much by his using--says 10-flat to me.
But it's possible. There is Obikwelu as a precedent--6'5", good body type, 10.1x normally-trained, 9.9x well-trained, dipped down to 9.86 PR once. And there is no particular reason to suspect that Obikwelu hasn't always been clean.
So ultimately, it's hard to tell. What I do believe strongly is that Bolt has used. Whether his 9.9x normally-trained baseline is due in part to that use, I don't know. What I do know is that he is always a threat, and should never be underestimated. It should always be assumed that he will go 9.6x when it counts, if he doesn't trip.