In late 2002 I was on a BA 757 inbound to Terminal 4 landing on 27L, we came off the runway on the old RW23 at what is now S4 I believe.
It was a bit of a struggle to stay in the seat with the force of braking that was used!!! Lap belts aren't the best for that!
Sitting by the window on the left hand side of the aircraft I saw the reason why we came off so quickly, a 747-400 was just about to touch down after we had vacated.
Would be impressive seeing a 747-400 do that!