In All Out War, the excellent account of the EU referendum campaign by Tim Shipman, there are several occasions where Tim relays the idea that the Leave campaign were happy to continually stoke the row over the £350m figure. The argument goes that every time it was discussed, even if the discussion was simply about how false the figure was, it reminded people of one of their key messages and, given they won, it is hard to disagree with their logic.
I was reminded of these passages today when listening to Vince Cable's speech at Liberal Democrat conference. Because there is a distinct risk that tuition fees is going to become a yellow-rosette wearing version of the infamous slogan on the side of the bus, and not in the successful way it proved to be for the leave campaign.
In economics, a subject Vince understands infinitely better than me, there is what is known as the sunk cost fallacy. This is the idea that the more you invest in something the harder it becomes to let it go, even if letting it go is in your best interests, be those business or political.
The tuition fees policy that doomed the Liberal Democrats at the 2015 election was put together by the Business Department that Vince ran. He stood and argued for it in Parliament. He voted for it. He therefore, perfectly logically, probably feels a degree of responsibility for the damage that it caused politically, which is possibly why he keeps bringing it up so often.
In the run up to Conference, the top line of his interview with The Evening Standard was focussed on tuition fees. In his speech today, a prominent section was dedicated to the policy, with Vince saying:
The solution Vince has proposed is a policy review led by former Cambridge MP David Howarth.
A perfectly laudable path to take, but one whose continual airing simply reminds voters of their most negative perception of the party. Just as each discussion of £350m for the NHS reminded voters of a key Leave message, every time a Liberal Democrat talks about tuition fees, even in explaining our attempts to fix our errors, voters are reminded of perhaps our most memorable contribution to coalition government. For the former, that was a good thing, for the latter it is most certainly not.
So my plea to Vince would be this. Run the review, change the policy if you want to, put it in the manifesto, answer questions about it if you have to, but for God's sake, stop volunteering to talk about it.