Might have flown a little too close on my descent. We were both on the same arrival track into dulles. We were right on top of each other. I was at FL430 and he was at FL380. so i had to slow down and kinda drop behind him so i could follow my descent. turns out we(just me) raced to IAD.
here he is basically within touching distance (very frowned upon)
OTHH - KIAD a359