Georgia has an off and on again relationship with "speed traps," with South Georgia implementing a "Yankee Tax" on folks headed to Florida, and most notably with Pine Lake, a DeKalb County city (a real one) of under 800 residents.
Laws were passed.
Now there are very limited situations where a speeding ticket can be issued at less than 10 over: by Ga State Patrol; or when the speed limit sign includes "strictly enforced." The latter seems to have all but disappeared in Georgia, but it is of little matter. At least in Dunwoody.
These inconveniences did not deter some dunderhead from pondering the impact, presumably beneficial, of lowering speed limits within Dunwoody (clearly not to include I-285). This was either trolling or serious lack of observation skills.
Are the flashing "yield" signs at the entrance to Nandina effective? No.
Is the re-jiggered 'T' intersection at the exit from Nandina lowering the number of rolling stops? No.
Why might that be?
Could it possibly be that without enforcement drivers are not going to pay attention to these signs? Do you think they would pay any more attention to lowered speed limit signs than they do to the ones in place now? Do you think this city is ever going to use real, live patrol officers to enforce traffic laws inside Dunwoody?
Cops around here don't even run cruise lights, do you really think they're suddenly going to care about any traffic violations?
So, can we make Dunwoody a speed trap? Hardly.