The responsible authority should put the limit at the 85th to 90th percentile speed, unless there’s something in that stretch the explicitly merits a lower limit. Since commasense didn’t say otherwise, it sounds like revenue generation to me. Hey! Maybe that the explicit reason for meriting a lower limit! 
Well, given that that photo alone shows one major curb cut for a large area of businesses, at least one of which involves tractor trailers, and there are other smaller curb cuts as well, perhaps they have it at 35 for a reason? 
But I’m not going to debate speed limits; that can be done in GD. 
All right, Mr. Northeastern-Ohio-defender-of-DC-traffic-bureaucrats, tell you what. Next time you come to Washington, give me a call. You can take a break from sightseeing for an hour and you and I will go to that block on New York Avenue. We’ll each have a roll of quarters, and every time we see a car going faster than 35 mph, you’ll give me a quarter. Every time we see a car going at or below 35 (that’s not stopped or slowed for a light or traffic) I’ll give you a quarter. I predict I’ll have your $10 in less than five minutes. 
I’m not saying that the traffic officials may not have a rationale for 35, but no one observes it and, as Balthisar said, I think the biggest reason for not making the speed limit more realistic is the money they make on the speed trap.
<giggle> Um, well, given that we are talking about DC, I’m not gonna argue the point. :eek: