note speed is your friend
I watched the video below, the one with mostly clean lines, and i agree with your observations, (R to L momentum over the ledge, keeping to left over ledge, keeping weight forward, etc.) The worst lines were over the right of the ledge with no momentum. Like you, i won't be paddling there in this lifetime, but a lot of folks made it look pretty easy. Some of the folks with bad lines look liked they were unfamiliar with the rapid, or maybe lost their bearings and hesitated above the ledge losing all momentum or even broaching.