LibDems' Cable doesn't do promises

In a BBC interview on Sunday 21 Nov Vince Cable, displaying tricky footwork insisted

• The pre-election pledge to oppose any rise in tuition fees was not binding;
• That the coalition's plans to increase fees did not make the Lib Dems' untrustworthy;
• That the Lib Dems "haven't betrayed anybody";
• The LibDems didn’t break a promise; 
• It is simply a matter of political judgment.

Why then had Clegg  said before the Election raising tuition fees would be a "disaster". 

Cable thinks a lot of the protesters don't understand the proposals, and anyway they only affect people who start going to university in a couple of years' time.

So, if it doesn't affect you shut up. So much for principles!