Probably because the stat about effectiveness was at the bottom and the title was "we're testing," not "here are the results of our test." I'm saying it's difficult to enforce because I see people ditch these things in the street a lot. Yes, I'm one of those "evil motorists" this sub seems to hate, but I dislike these things because a) they're hard to see at night b) they get ditched in the roadways and driveways and c) they care about as much for traffic laws as cyclists do (e.g., blowing through reds). Corralling them is great, if you can get people to do it.

I'd be more interested in the stats for the "non-hub" areas.