Basically I like to see a performer looking relaxed. If you are uptight about what you are wearing, then you will be uptight about your performance. I used to love wearing my choir robes (very British, very traditional cassock and surplice) because it meant I could be comfortable underneath. When I've sung as soloist at non church functions I've had to wear a posh dress, and felt that it inhibited my performance, because I had a) no pockets to put my hands in when not holding a book. b) to be careful as I breathed in (especially in one particular dress, a good deep breath popped a button - just as well they were at the back!) in case of unnecessary exposure or straining, and c) I'm never comfortable in a dress anyway.

LTS