If you think about it, though, it would in principle have been possible to maintain the slogan if Ed Davey had committed the Liberal Democrats to take Britain back into the EU as soon as possible. It would have been dishonest in practice because there is zero prospect of a Lib Dem government, but nevertheless it would have been a way of holding the line. That option has now been removed, because Davey has sheepishly confirmed that the Lib Dems will not be campaigning to rejoin the EU, and will instead merely be seeking a close relationship from the outside.
From a UK-wide perspective that makes perfect strategic sense, because it means that the Lib Dems can still be "the most pro-European of the main parties" while no longer being in a state of outright war with Leave voters or with the referendum result. But it leaves the Scottish Lib Dems in an awful place - they said they'd never choose between the UK and the EU, but they have, and it's the EU they've rejected. Actually it's worse than that, because the decision has been made for them by their boss in London.
There's now a golden opportunity for the SNP to make some ground next year with pro-European voters in pockets of Lib Dem strength. Much will probably depend on whether the Lib Dems succeed in convincing people that formal EU membership and a close relationship is not that big a difference. That'll be a tough sell, I suspect.
* * *
Just to think wildly out of the box for a moment, the recent turmoil in the Scottish Labour party has led me to wonder if it's ever occurred to Nicola Sturgeon to put feelers out, and discover whether one or two key figures within Labour might be interested in taking Cabinet positions in return for joining the pro-indy side. It's a long shot, but if it worked it might finally break Scottish Labour and be a decisive tipping point for independence. And never underestimate personal ambition - how else could some of these people ever hope to wield power? They wouldn't necessarily have to defect to the SNP - a model could be the way the Labour government in Wales co-opted the former Plaid leader Dafydd Elis-Thomas (he became a junior minister as an independent).