No need to get all upset over things in the past. People have reacted to Scott's behavior with predictable results.
It was great hearing an explanation from Doug, and it is a valid and believable one, IMO. However, because of Scott's past every time he acts differently drugs are always going to be brought up. Not saying its fair, but it is a natural and understandable reaction considering his lifelong public battle. Lets also not forget there have been a lot of times where Scott has pledged that he is sober, when he was in fact not (12BB tour and a couple others being ripe examples).
I do agree with you, however, and choose to believe Doug's confirmation of Scotts sobriety. I want nothing for the best for one of my idols and (IMO) the best performer/frontman. I'm so very glad he is staying clean and away from cocaine/heroin.