I highly doubt it is supposed to be this way that when you close the tab you don´t get the loss in your statistic, therefore this has to be considered a bug. And I am damn sure that somewhere around i read that (like in any other game I know) abusing bugs is to be punished (on rightfully so), so Anarook at least did good to keep the risk for shileka and others with the same problem as low as possible to get banned for something they should not have done.
when you close the tab, leave the other tab open, then close the 1st tab....information in the 1st tab although saved will be overwritten by 2nd tab's if you save it. I see nothing wrong in it but certainly, what the point? You have to be a really 'free' guy, lotsa time to waste, open tabs, save, lose, quit, save....how much time will you lose? Although do not agree with such, but if it's not (edited*)stated as a rule, then it's not wrong.