This week's boundary changes defeat is, surely, the moment the Conservatives learned to hate the Lib Dems.
It was a truly unprecedented moment for this great experiment in coalition. Liberal Democrat ministers, led by the deputy prime minister, marched through the division lobbies with Ed Miliband and Labour MPs to vote down boundary changes. Doing so helps Labour, because it takes away the 20-seat advantage the Tories would have won from the reform.
At the heart of the bitterness now infecting coalition relations is a disagreement about the 'deal' the two parties actually had in 2010. I've explored that this week with contributions from seething Tory backbenchers Peter Bone and Eleanor Laing on the one hand, and the Lib Dems' constitutional affairs spokesperson in the Lords, Paul Tyler, on the other. Casting a gleeful eye over the whole sorry mess is Wayne David, Labour's shadow constitutional reform minister in the Commons.
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