That does make any sense, actually, assuming Notpad runs on 3 fps and every input takes 2 secs to process.
Go on, buddy, drive fast, hit the wall…hit the fps wall… be happy and all fine and dandy until then, push the pedal…yippee!, everything is pink flowers and candy 
The only reasom why there are no statements from UE4 Devs yet is because they know they are behind with essential multithreading. I mean look how they try to incorporate async in the physics tab in the Project settings…experimental… I mean, you tick it and the Editor crashes. They know they are behind…they know…believe me.