I'd be ecstatic... and so supportive, I'd install a pole and a light show in our bedroom. ;-)
I have seen such a class a few times at a gym preparing a class of my own. Looked sexy as hell.
I would build a pole dance stage in our sleeping room
There is no reason why any man should be bothered if there woman was socialising with other women, having fun, and exercising at the same time. It is only when the workout become a performance for a crowd that might be a problem for some men. Personally I wouldn't mind if it was just a work out but if my partner performed for a crowd I wouldn't be happy, as she would be wearing very little at performing sexy moves, for me, that should be for my eyes only
I personally don't think my woman would ever need that.
She wants to be a stripper. Leave her now! Haha just kidding. There are tons of girls who want to learn their way around a pole. Makes us feel sexy. No need to be worried, be supportive! And maybe she'll show ya what she learns :p