A delta-V limit would be “constant” in that the teenager would build it into their mental model of how a car drives, and take it into account if/when exceptiona

A delta-V limit would be “constant” in that the teenager would build it into their mental model of how a car drives, and take it into account if/when exceptional circumstances do occur. The greater risk comes from the car spinning out of control from a standstill because of enthusiastic acceleration. As for safety, it’s not often we need to outrun a pyroclastic cloud/tornado/airplane crashing into your path.