On Monday, I watched an R6 rider: sneakers, shorts, t-shirt, full helmet, coming the opposite way and looking over his left shoulder. He drifted into the left turn lane.
On my left, a lady and her pal, chatting it up, signals for a left and starts to move into the left turn lane.
When they passed, each halfway into the left turn lane, there couldn't have been more than inches between them, and I don't think either one saw the other.