The biggest flaw in his calculation is that he's a groupbuy customer - not an average customer. So it's kinda misleading when he runs around screaming "it's not profitable" when it really is for the average customer. Groupbuyers ALWAYS overpay.

And your few bucks, could possibly be in the thousands. Kinda hard to see the difficulty doubling every month... forever.

Groupbuys are good for the people who don't want to risk the full amount or don't have the money available. The bad thing about groupbuys is that they're highly risky (the owner of the miner can just disappear and nothing you can do about it), you overpay for GH/s and have to pay some fees. They don't represent the average customer.