It makes changing tubes so easy. A lot has appeared in the press lately about the quality of unbranded inner tubes, usually relating to poor vulcanising around the valve. The tube I took out was not unbranded, but wasn't one of the big names. It had a small split along one of the mould lines:
Its under that blob of Tyreweld. All fixed now, with a nice new Michelin tube from Vintage Tyres.
Oh, and it started first kick (well, first enthusiastic kick)!