No, Heathrow hasn't opened a waterslide. We just noticed that we've traversed a lot of tubing to arrive here at our Star Alliance Lounge. The first walk was several hundred meters in the tube connecting the Hilton to the terminal. We then made our way down in the elevator and walked along another tube to the Heathrow Express and rode to the stop for terminals 1, 2, and 3.
We then tubed another 300 meters to terminal 1. In a few minutes we're going to board another tube and spend today flying LHR-ORD-PDX-SEA. That would be London Heathrow to Chicago O'Hare to Portland to Seattle. A long day but a lot more miles in the bank - and we actually enjoyed our walk.