Fair point, however I admit I am a bit of a cynical bastard and so suspect that most politicians would swear the earth was flat, if they thought for one second it would extend their time in power.
That is main reason why he (Polish PM) has to be very wary now - if he didn't back down from ACTA he wouldn't stand a chance in next elections. And there is still some time before we will have them but if he makes more blunders it will be his political death.
I still don't like him for his other decisions, and the lies he told about ACTA before he changed his mind, but at least he can say he was wrong.