[stephen_g]

I think it depends on the context. If you're a talented musician or you want to do stand up comedy or something it can be super useful to pretend to be a more confident version of yourself while you're performing. It goes on, you perform, it comes off. I've found the more you perform, the less you have to pretend and eventually you can just can be confident (it's basically just exposure therapy), but it's hard to bridge the gap to get up at all. And that's not even mentioning what actors do, where it's expected that they're pretending to be a character!

Obviously if you were consciously putting on an act to appear to be a completely different person just for a relationship, or all day, every day at work then that's not healthy.