Whatever the reasons he had for posting it to his Instagram, and then deleting it, are unknown. I'd wager a guess that the deletion occurred because of his lack of commitment to the nudity. If you're going to post a nude selfie, at least shimmy the jocks down towards the knees and out of shot, James.
Either way, if this isn't an open invitation for Lindsay Lohan to break into his hotel room again, I don't know what is.
We're with Marie Claire on this one... he's not crazy, he knows EXACTLY what he's doing... apart from the jocks part. And maybe add some soft lighting next time.