[jasonturbo]

I would suggest that a reasonable person cannot gauge the speed of an oncoming vehicle nearly as accurately as they can gauge the distance of the oncoming vehicle. For this reason, we likely develop driving habits primarily based on estimating distances not speeds, consider how many times you've gone to turn and at the last minute stopped because you realize the approaching "speeding" vehicle is travelling much faster than the other vehicles on the road at that time or during historical instances performing the same maneuver at the same location/time.

With respect to this specific accident, consider that there was two vehicles approaching the intersection from the direction opposite of Dr. Hui, the Audi and what appears to be a Chevrolet Aveo. Consider that the Audi was travelling at approximately 3x the speed of the Chevrolet Aveo, if you look at the dash cam video you will see that at 12 seconds both cars are clearly in the right of the screen with the Audi approximately one car length ahead of the Aveo - the impact then occurs at 13 seconds, one second later.

If Dr. Hui gauged the speed and distance of the Aveo (The vehicle nearest to the intersection at that time) at the 10 seconds mark of the video and initiated his turn, he may have, under normal circumstances, cleared the intersection before the approaching vehicles arrived. The Aveo arrived at the intersection at 14 seconds, suggesting the maximum time period Dr. Hui had to initiate his turn and clear the intersection was 3-4 seconds... which seems to be enough.

Perhaps this doesn't get the point across, but I would suggest that we can assume Dr. Hui's car and the Aveo were being driven by reasonable people and we can use that as a means of determining whether or not the accident would have occurred if not for the excessive speeding of Mr. Chung.

Disclaimer: Excessive use of "thumb suck" mathematics above