Reactions in the party to the news that both Plaid and Renew may be backing Jane Dodds and the Liberal Democrats in the Brecon and Radnorshire by-election have included quite a few mocking comments.

Given the checkered history of Renew and its electoral performance, a bit of joke-making about the degree to which their backing will matter is understandable. And I’ve not been averse myself to poking gentle fun at the troubles amongst would-be new pro-European parties.

But it should be no more than that. Where gentle humour becomes condescension, rudeness and ridicule, it becomes misplaced.

One reason for that is simply a matter of good manners. Being polite and welcoming to people who have decided to back a party is the decent thing to do (unless of course it’s a brief tactical backing from someone who otherwise is all at odds with what you believe).

It’s also the self-interested thing to do. If you react to someone supporting you with ridicule, how does that look to other would-be supporters?

Finally, there’s a broader political benefit to be had from people backing you than can be measured simply by how many votes they got in the past. For the Liberal Democrats in particular at the moment, having a mix of differernt people or parties urge Remainers to vote Lib Dem is important in itself.

That sense of a broader coalition coming together behind the Liberal Democrats was an important factor in the European elections triumph. We should welcome signs of it happening again.