I've had similar experiences of BT efficiency myself on two recent occasions. This policy of keeping you in touch with their progress is wonderful; in both of my cases I had problems with a landline, and in one instance the engineer rang me on my mobile to tell me that he was in the exchange fixing the problem. He rang back an hour later to tell me that all should be well (it was), and half an hour later he was at the door, checking that I was happy with what he had done.
Bt seem to have realised that we will all be a good deal more understanding about glitches if they keep us in the picture. They are a communications company - one of the best in the world when it comes to innovation and technological expertise - and they understand that people get angry when they're left in the dark.