Nobody knows. That's the point. Historically he was of the Bennite left who were anti-EU, seeing it as antithetical to industrial workers interests, and a capitalist bloc. This has led to much confusion from the current socialist Labour leaders who can't quite get the right angle on it, as that old constituency no longer exists except to vote UKIP, Tory or not at all. It's a mess.
It's also a mess for the Lib Democrats who seem unable to make any ground on the anti-Leave vote despite being the only really credible and outright pro-EU party. I understand that, though, they have always been a joke.
It's really interesting that this whole thing has been turned on its head this week by the manifesto launches which is why I don't discredit Droid's hunch, though I find it unlikely.
Droid will be relieved to know that I have no hunch for this one. I'm confounded.