wait for the fucking confirmations and you will be fine. stupid ass developers deserve their exchanges and services get DOSed if they make all kinds of false assumptions.
I completely agree, but I've also learned from my experience running a (small) software company that you can't expect the users not to fuck things up. If anything even remotely resembling a flaw exists, users will find a way to break it, even if unintentionally. Bitcoin would ideally not be in a position where they have to rely on people/exchanges not fucking up, because they will.