Roundabouts are so manageable if one drives the posted speed limit. One of the selling points of roundabouts is the fact that one cannot have a major collision if one is travelling 15 mph. In Carmel, a few of them are small, and speeding complicates them immensely. Example: Range Line Road and 136th Street (Smokey Row.) If one is traveling south at the same time the high school lets out, it is next to impossible to enter the roundabout due to the westbound traffic travelling at a rapid pace. This happens during the rush hour all along Hazel Dell. A speed bump would be very practical to controlling this.
Turn signals in roundabouts work very well. They tell the traffic yielding what you are doing. Also, one cannot go straight on a roundabout. Once you enter it you are driving in a circle or multiple curves and must exit at some point on the compass.
Enforcement of speed limits and speed bumps would solve a major portion of the problems on our wonderful roundabouts.
Charles Ray Harmon, Carmel