I look for lane positioning to see if the person in front of me is doing a u-turn. We have mostly 2+2 and 3+3 roads and almost everyone drives these big clunky SUVs and massive trucks. They’ll turn from the furthest right part of the left turn lane and still need the whole road and the merge lane to spin around. Conversely, people turning left tend to sit in the middle or on the left of the lane. The bigger problem is many don’t realize that a u-turn must yield to all other movements.