There's a 6-way roundabout I know of that frequently has one of the 3 intersecting roads dominate the traffic, so people just go full speed from that road. In that case, the other roads can be completely starved, so a 6-way stop would have been better for those roads in those times.
As for t-boning, you can definitely have someone enter a roundabout early/late and hit another car on the side, or dart in front of a car that's in the roundabout (especially possible if the roundabout is not perfectly circular) and themselves get hit on the side.
And people manage to go "out of turn" in roundabouts all the time, by not yielding, or by tailgating.
As for t-boning, you can definitely have someone enter a roundabout early/late and hit another car on the side, or dart in front of a car that's in the roundabout (especially possible if the roundabout is not perfectly circular) and themselves get hit on the side.
And people manage to go "out of turn" in roundabouts all the time, by not yielding, or by tailgating.