I think the idea of 'poisoning brands' in terms of a political party is old hat now. It seems to be easier than ever to come back from the hole. Look at the Libs after 07 election - floundering around (remember when Brendan Nelson was the leader?) and looking like they'd be in the wilderness for a long time. Three years later and Labor only managed to form a minority government by the skin of their teeth. Next election they were gone.
Then after '13, the Libs looked in total control - Labor had apparently 'poisoned their brand' so much that the Libs were a shoe-in for the next election at least. And now here we are.
Honestly, I think it's a bad development. As if politicians weren't short sighted enough before, things can change so quickly now it's basically impossible to get anyone to govern with the long term future in mind. We really need to change to four year terms.
Funnily enough, it seems to have happened due to two people with seemingly very similar personalities and governing styles, Rudd and Abbott, completely failing to govern as part of a cohesive party. Dudes need to realise we don't have an executive branch in Australia.