"No, posturing against us would be the logical outcome of us pulling out. Look at how they reacted to the Lisbon Treaty referenda. Look at how they react to the Conservatives’ pulling out of the EPP. Not conciliatory. Not in their own economic interest."
Our scepticism would no longer be a threat to ever greater union, and there would therefore no longer be a reason to punish it. If they wanted us to return to the EU, the very worst thing the remaining EU members could do would be to lash out at the British public.
So your case, essentially, comes down to the idea that the remaining members would be stupid enough to lash out, in pride, at us, despite that being entirely counterproductive. And, that they could sustain that position despite it adding to their already high levels of unemployment and making a lot of valuable voters poorer.
If you really think that the EU will act in that way. I'm surprised you are willing to have anything to do with such an institution. Surely that level of blind stupidity will also render them deaf to any calls for reform?