For the first time in ages, and mainly because the wife needed the car,
I took the Tube to Heathrow, and not even the Heathrow Express. Journey
both ways was Dalston Junction, Whitechapel, Barons Court, Terminal 5.
Not only was it fairly painless bar some overcrowding on part of the
District (Chelsea at home on the way out) the off peak fare is only
£2.90 each way, much lower than I thought, as I've found from checking
my Oyster history.

E.