You play?acsguitar wrote:You are not going to warp your guitar in a short period time. You should be fine leaving it tuned like that.
Necks take a huge huge amount of pressure. You will be fine. I'd worry about humidity more then tuning pressure.
I've been playing for 13 years
Your guitar should be fine, but know that it'll make your other 5 strings slightly out of tune every time you tune up/down.