Properly sited roundabouts don't need lights. Anyone who "detests" them must not live or work near busy intersections governed by stop signs only. The town I'm working in now has two roundabouts and one 4-way stop. Morning and night, the 4-way stop backs up traffic for blocks, while traffic flows through the roundabouts without issue. The city council has set aside a million dollars to change the 4-way into a roundabout this coming spring.
There are lots of stoplights that should also be replaced by roundabouts. A solid line of traffic flows right through a roundabout, and most of it is delayed by a stoplight.
The only problem with roundabouts in USA is the 30% of drivers who don't know how to use them, and stop when they see the yield sign... don't be that driver.
As an American, I detest how other Americans use them. Some folks in the 'ring' slam on their brakes when they see another car approach. Others will randomly pull out in front of folks who are already in the 'ring', causing the first group to always slam on their brakes when they see someone approach. This causes the second group to always pull out into the 'ring' without yielding right of way.
No one uses turn signals on them, and you never know when, where, or if someone is going to turn. It's haphazard maneuvering. 4-way stops are far more predictable and functional.
Your first comment is accurate, no one uses turn signals in any of the ones I use on a daily basis either, but that doesn't make them inefficient. In fact I think it keeps everyone on the defensive, and makes them pay more attention before entering.
But as I said in an earlier comment, the reason they kind of suck in the US is we don't seem to do them right.
* A very wide circle (350ft/100m minimum) with 3 lanes
* Each entrance and exit has 2 lanes.
* The outside lane of the circle directly connects the outside entrance with the "first" exit.
* The middle lane of the circle and the inside lane of the entrance allows you to exit at ANY of the exits
* The far inside lane of the circle exits nowhere without a lane change, but allows you to bypass an exit that might be backed up due to traffic.
Huh? That's only feasible for intersections of large roads, but American four-way stops are usually on small(ish) residential roads, where single-lane roundabouts work just fine.
No one is saying that roundabouts should replace ALL intersections, and the few they have in small residential places operate just fine with a single lane, but I'm skeptical of their value over a proper 4 way stop or a 4 way protect turn light.
