Same story on Crystal Dr. Occasionally they put up a variable message display warning drivers not to block the bike lanes. Once in a great while I’ll see ACPD there, presumably writing tickets (or issuing verbal warnings.)
I’ve given up trying to use bike lanes in either location. Crystal Dr. a complete clown show, with double-parked cars and drivers jockeying for position, and the occasional U-turn from the northbound lane, just for extra thrills. Luckily it all happens at low speed, so likely to be more annoying than lethal.
Another LOL variable message display is on Rt 110, adjacent to Arlington Cemetery bike path. “NO LOUD MUFFLERS. IT IS THE LAW!” I’m sure that’ll snap the scofflaws into compliance.