David Cameron has been careful not to set any red-lines for his negotiations on the UK's EU membership. Personally, I suspect this is so he can spin whatever he gets offered (if anything) as a success.
However, another question that has now been raised is whether the changes he claims to get will actually involve any treaty change at all.
Treaty change requires unanimous agreement of all EU members - not only is this unlikely, but it is unthinkable that it could happen in the time setout by Cameron.
If there is no treaty change, then nothing has really changed... if anything is agreed it will be informal and reversible at the whim of the EU commission.
A third-way has been suggested, which involves the EU agreeing now and then passing laws retrospectively applying the treaty changes(!). However this fails on several levels all by itself. Firstly the UK referendum would be on a "promise" of change... given all the broken promises before we actually go this referendum only a fool would trust Cameron and the EU now. Secondly, it has been suggested that this method would avoid other members having to have referenda etc on the changes... As if this is a *good* thing! If the EU considers trying to bypass its other members democratic processes in this negotiation, what does that say about how they will treat the UK's democratic process in future?
The negotiation time table has already failed, the negotiation is worthless, there can be no referendum with out a new relationship to have the referendum on - as *that* is what was promised. I think the referendum may be off...