Have yet to see the highlights of the final session but appears as though Sidebottom was brilliant. Raises the question why he was stuck playing county cricket for the last six years...
Well, for part of it it was because he wasn't terribly good, and there were better seamers at his own county. He joined Notts in 2005, and when the likes of Plunkett (who can bat, a little bit, but can't bowl) and Mahmood (who can't bowl... at all... really... and is highly unlikely ever to be able to) were picked ahead of him there's some air of extreme mystery there.
Nonetheless, had he been picked in 2005\06, 2006 or 2006\07, I honestly wouldn't want to vouch for how successful he'd have been. The cricket-balls used in 2007, when he finally returned, were the best cricket-balls we've seen since 2000, the first time they've really swung like they should in this country since then. And he came back to Test-cricket at Headingley, a very seam-friendly ground. These two factors gave him a head-start, and allowed him to get a foot in the door in a way he might well not have done otherwise.
On that subject, BTW, just noticed that Sidebottom wasn't that far away from having 2 hattricks this match.
Had he got a wicket with his 1st, rather than 3rd, ball of the second-innings, he'd have had one before he got one, so to speak.