Obvious title is obvious.
Every year, the DC area cyclists en masse go and ride loops around Hain’s Point. It’s flat, it’s cold, and it was unusually un-windy.
I got passed several times by a large group of riders (40+ riders), helping me experience what it means to be in a slipstream. I think partially because of that (and the bait to keep up with experienced folks on road bikes), I rode my fastest 5 and 10 mile marks (also helps that it was, as stated above, flat, and still.)