Former McLaren and Ferrari Formula 1 driver Stefan Johansson has labelled the current engine regulations as "ridiculous" for not allowing enough development to help rivals catch Mercedes.
The German manufacturer has dominated the championship for the second year in a row, as its power unit has proved to be a class apart.
With in-season engine development limited to just the tokens granted to each manufacturer, Mercedes has managed to keep its clear advantage for two years now.
Johansson, who raced in Formula 1 from 1980 to 1991, reckons the concept is "completely broken".
"The real problem is this incredibly complicated engine formula that F1 has with penalties for this and that, and you're not allowed to do any development," Johansson said.
"It continues to make no sense to me. The development ban was initially implemented to keep the cost at a sensible level, but that concept is already completely broken.
"The manufacturers have spent so much money on these engines it's obscene. Why not just let them carry on developing them and at least be able to fix them?
"It's ridiculous to have a formula where there's only one successful engine and the others are not permitted to do the development they obviously need to become competitive."
The Swede believes that limiting engine development but allowing teams to spend as much money as they want on developing the chassis does not make any sense.
"Yet you can bolt 500 new pieces on to the chassis every weekend if you want," he added. "The top teams do that of course, with crates of aero-parts flown in everyday in a never-ending development war with their chassis but you still can't touch the engine.
"It's nonsense. If you were allowed to throw everything but the kitchen sink at the engines as you are on the chassis, I am sure that Renault, Honda and Ferrari would all be better - maybe not as good as the Mercedes but certainly a lot closer.
"With these rules if you don't get the engine right out of the box there's really almost no way to catch up and you're just screwed.
"If your engine is as wrong as the Honda is, what do you do? You're only allowed X-amount of upgrades. On top of that, you're not allowed to go testing."