My fix, just use the same in car system they use to alert the drivers to a SC deployment to tell them to engage the pit speed limiter. Everyone must engage by a certain amount of time(maybe 5 seconds) and from the time the system is deployed no passing is allowed, any passes must be given back and if not then penalized.
Having everyone at the pit speed limit will lower the speeds thru which they may drive thru an accident scene, they can always go slower if necesasry. Since they are all at the same speed all relative gaps will be somewhat maintained so we wont have a huge bunch of cars entering the pits at the same time like we do now when they bunch up behind the SC. Pits dont have to close and double stacking will be minimized.
Am I overlooking anything? Seems like such a simple fix to a huge problem. Only problem I can think of is overheating, but after seeing Massa stand still for so long this weekend they should be ok moving at 60kph in seventh gear.