As we move into party conference season, so we also enter the world of the official campaigns for the EU referendum. Both Remain and Leave sides now have their contenders for official status in the throws of activation. This notwithstanding the continuing lack of clarity about what’s being renegotiated or by when: the calculation has clearly been that to wait for the outcome of Cameron’s negotiations will be too late to make a difference on public opinion.

With this in mind, it is perhaps useful to consider the dynamics of group formation that are taking place.

The referendum format is an unnatural one, in that it requires there to be only two options: yes/no, in/out, remain/leave, whatever. I’ll not bore you again with my problem with such reductionism – short version: there are many ways of conceptualising and addressing any issue of public policy, let alone one of the scale of the EU – but precisely because it does reduce matters to those two options, it also forces together political actors that would not normally sit together, figuratively or literally.

Groups and individuals see the question, take a position and then find themselves in strange company: it’s rare to find examples of them doing it the other way around – seeing who’s on which side and then choosing. Indeed, I struggle to give you an example at all.

Instead, there is a counter-pressure to fight for one’s preferred outcome, but to do so at arm’s length from those one dislikes.

Organisationally, that looks messy: a multiplication of campaigns, duplicating outputs (and so wasting resource), contradicting each other, or missing out particular audiences all together. In practical terms though, the costs look much smaller, because they can contain the associational costs of voting a particular way: “I’m voting in this way, not because of that terrible group X, but because lovely group Y really made the case.” At some point that breaks down, especially if everyone on one side looks tricky or marginal (as arguably happened in 1975), but we can certainly how that might play a role this time around.

Thus the coherence of the two campaigns might not tell us very much about the outcome, but is still worth considering, for what it tells us about the structure of debate on the EU and about the paths from the referendum in the coming years.

The two basic dimensions to consider here are intensity and direction of attitudes. The former is the degree to which the position is a central part of an individual’s or group’s identity and beliefs: since there are very few who see the EU as THE central issue, instead of just a manifestation of some wider problem, we would expect there to be a wide range of ‘how bothered am I by this?’ positions. The latter captures the equally wide range of ideological and practical positions on European integration, as I’ve already mentioned.

With these dimensions in mind, we can see that the Leave campaigns cover a much broader set of directions (from radical left to radical right, to use that language), together with the greater set of deeply convicted/intense activists. By contrast, the Remain campaigners tend to be more moderate in their politics and their intensity: Tim Farron’s speech to the LibDem conference is about as strong an evocation of the value of the EU as you’ll hear.

This suggests a couple of points.

Firstly, the Remain campaign will find it easier to share core messages in the coming debate and to create the impression of a broad church behind membership. The Leave campaign will be more fractured, but also more able to pick away from different directions at the Remain arguments: broad coherence is not cost-free.

Secondly, it suggests that if there is a vote to Leave, then there will not be a clear strategy for what comes next, merely another set of discussions about the options. As has long been clear, disliking the EU is not the same as agreeing on what should replace it. Those fractures will become ever more apparent over time.