Double huge American flags with the tiny light on top of each
You think the guys driving TT and CL1 want to be racing at full speed and have to deal with lap traffic on the second lap? They're there to race and having 2 different races on the same day is the safest way to do it IMO.
Look what happened to the class 11 at the MINT 400 this year. It got hit hard and that was a longer loop.
Well the first group is the slower group and each lap will take more time compared to the faster group. It comes down to time, there just isn't enough in one day.