Fixed-term Parliaments Bill

I am grateful to my hon. Friend for giving way. The hon. Member for Aldridge-Brownhills (Mr Shepherd) did not give the key quote from Professor Blackburn, who said:"““It is likely that the Coalition's concern with concretising its political alliance, and having the longest period possible in which to implement its tax increases and cuts in public expenditure and then recover sufficient popularity in time for its next meeting with the electorate, has affected its judgement in this matter.””" Is it not politics that is driving this rather than any grander constitutional vision?