Clegg's unusual speech act (follow-up)

Several people have pointed out that Clegg's apology is not for breaking his promise, but for making it in the first place. Rather an unusual speech act. Julia Hartley-Brewer's comparison seems apt:

Nick Clegg's apology for breaking tuition fees pledge is like a husband saying "sorry for my affair, next time I won't vow to be faithful"

And.. no more UK politics here for some time, I promise.