"Why we run restrictor plates is so the cars stay on the ground," said Johnson "It doesn't matter the kind of race car. If it's off the ground, you cannot control it in an accident.
"Roof flaps help, cowl flaps, getting the wing off the back of the car helped [in NASCAR],” Johnson said. “There is a threshold for all the cars where they're airborne. And as we go to Talladega with a larger restrictor plate, we get closer to that threshold - that gets us closer to that lift-off point.”
The open-wheel nature of IndyCar also contributed to the Vegas accident, from what Johnson saw: "In that crash, what got the cars off the ground was wheel-to-wheel contact ... The open-wheel vehicles, whenever they touch wheels, it climbs them and just catapults them and throws them up.
"It was cars climbing other vehicle's wheels. Having so much speed, they came in and just jumped off the back of another car. Some of that can be the structure of the vehicles and the way they're shaped, but I think the majority of it was tyre contact, jumping off each other."
The new 2012 IndyCar Safety Cell Dallara chassis - that Dan Wheldon himself had been leading testing on in recent months and which will now be dedicated in Wheldon's name - has new features to stop cars getting airborne so easily, and also incorporates controversial "bumpers" into its aerodynamic body work protecting the exposed wheels that have been unpopular with fans on aesthetic grounds before Vegas.
The catchfence was another problem highlighted by the tragedy, as Johnson pointed out: "That fence is so nasty... It shreds cars apart," he tweeted to Paul Tracy on the social messaging network.
While massive improvements have been made through the introduction of the impact-absorbing softer SAFER barrier system, the catchfence remains the single biggest threat to the integrity of a car involved in an airborne accident. After Sunday discussions have already been starting about how this could be improved in future.
But as Johnson's fellow NASCAR driver Jeff Burton pointed out, "You'll never reach safety ... It's not a goal [that you arrive at,] it's an effort," he added. "We always have to be working harder to make it better.
“The faster you go, the bigger opportunity for stuff," Burton continued. "The kind of pack racing they have there and what we do at Daytona and Talladega, it creates situations where you see spectacular wrecks. Anytime you have spectacular wrecks, you have the opportunity for bad things to happen.
“There's no question that our sport is the safest it's ever been," Burton added. “There is also no question that there are still things out there that have to be fixed ... We have to look and pay attention. I'll give the race tracks credit – the race tracks have invested an exorbitant amount of money on safety, but we're not there yet."