It's looking clear that Coyle isn't the genius he was being made out to be last season but like you say, you've got to feel sorry for him with the way things have changed for him at Bolton.
Lose Holden and Lee (that's his name, right?
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) to injury, Elmander on a free and Sturridge back to Chelsea, without any money to replace them, there's not much anybody can do.
Well, they were terrible WITH Sturridge's goals last year, they were terrible with most of those players last year. Sure its not easy to improve but their form dipped way before most/any of those players had a problem.
Only Holden got injured during last season and Bolton had already gone from first half of the year drawing a lot of games to second half of the season losing rather than drawing.
But as we've seen plenty of times, some managers don't suit certain clubs. Sometimes they work with a new no.2 and they just don't work well together. Different combinations of coaches and players. Sometimes player transfer work out great, sometimes they fail miserably. A great manager won't always be able to get results at any club with completely different people, players and coaches, around him. Likewise a not great coach could do very well with the right team/coaches around him.
Whatever your opinion of Grant is, and most people think he's awful, he somehow got Chelsea to a final.
Manager is one part of pretty big machine of parts, his style isn't working at Bolton, it doesn't mean it wouldn't work great somewhere else, infact, we know it worked pretty well somewhere else.
Redknapp all but got West ham and pompie relegated(through woeful transfers and ridiculous spending) but with a owner with a tighter leash around his neck not letting him spend a club into oblivion(or not yet
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) its working much much better.
I think Coyle and Bolton is working horrifically badly, the sum of all the parts there is NOT working, that doesn't mean most of the parts somewhere else can't do very well.