Would the commonly redundant phrase "tour-de-force performance" take hyphens as shown — yes or no? Thank you.
I wouldn't hyphenate it, and I wouldn't add the redundant "performance". http://dictionary.reference.com/browse/tour+de+force
I wouldn't hyphenate it either (although I guess it would be okay to do so). However, I don't think the "performance" is redundant. It may be a little clumsy. 'Her performance was a tour de force' may be more pleasing than 'She gave a tour de force performance', but out of context it's impossible to say how you would best write this.
I actually would use hyphens here because it's being used as a phrasal adjective. On the other hand, if you use it as a noun phrase ("The performance was a tour de force"), then I wouldn't use hyphens. This is purely a personal preference, however. You can choose to leave out the hyphens, and it would be grammatically correct.