After all the Yamaha controversy about the valves

Daft thing about that situation was that there was no "cheating" as such - it was just a paperwork foul-up.

Apparently the original supplier of the titanium valves stopped making them, so Yamaha had the valves made by another company to the same drawing & material spec. Then these "new" valves started failing, so Yamaha asked Dorna for permission to change them & Dorna threw a hissy fit as Yamaha had failed to inform them of the change of supplier between having the engines homologated with valves from the original supplier & building the actual race engines with valves from the new supplier.

So no "cheating" or intent to gain an unfair advantage in this case, just overcoming a supplier problem for the same parts and subsequent communication shortcoming that cost them dear.

Nigel B.