While his ability to direct a fight sequence in my opinion is fine, hopefully with the Avengers they get some good consultants in to advise what to have in the fight sequences, especially for Cap.
The operative in Serenity is about the only male I've seen him direct with some good fighting skills, and even then it was underplayed so he could either dominate or fight against brawlers (i.e. Mal). Whedon's love of powerful women lets us see great action when it's flexible women doing high kicks and whatnot, but I've never really been that impressed by dudes fighting in his work, its usually wide punches and stunted kicks, and thats just not enough in my opinion to make me go "wow". That said, I know Cap is from the forties and fighting wasn't exactly as refined and globalised then as it is now, so I'd expect a lot of tackles and boxing style punches, so I guess weave in some shield throwing in there and Whedon could at least do him justice.
Wow, that was a lot of ranting to get nowhere.
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