Re: Ha....
I don't know; seat totals aside Labour obtained a +1.4% swing over 2010. So if he wanted to stick it out then he'd have had a pretext. I imagine he stayed in not just to avoid becoming a story during the election (no doubt not just altruistically) but because had Labour returned to office then he could have done more inside than out.
That said, I don't see the benefit of walking away now and not just doing it quietly in a couple of years, unless he thinks that the slender majority means parliament may not go the full term and he could end up still being a party member for the next cycle.
But, yeah, you're probably right. Though if I were him I'd at least have waited to find out who the next leader is going to be.