The car rolls more than any other I've ever seen. I think part of that might have to do with how tall the top deck and other components are. It seems to be about 4mm higher than an XRay. And I agree, other cars stay much flatter. This is a much different approach. It seems to be working.
The Yok has been very fast on asphalt, but the team has had bad luck. Tamiya has the right car for that surface, and the team to go with it.