Although, in the grander scheme of things, the Tories leaving the EPP may seem a very minor issue, this is the one solid "Eurosceptic" commitment David Cameron made during his election campaign, one which was attributed to bringing the Eurosceptic wing on board. For him now to be unable to honour that commitment would have significant ramifications, reaching far beyond this immediate issue.
That apart, this is in fact quite an important issue. As the EU parliament grows in strength with the
The "colleagues" have but one opportunity to pull this off before the next euro-elections, and will thus bend every rule – which they have been doing – to get these rule changes in place. Bruno Waterfield did us a great service in bringing attention to what was going on, but the real threat has yet to be fully recognised.
UPDATE: England Expects offers his take on the affair.
UPDATE 2: Alex Singleton on the Telegraph clog sees problems for Cameron.