Toto Wolff used an expletive to describe his feelings about Ferrari's apparent engine power drop from 2019 to 2020.
Teams were already unhappy with Ferrari for refusing to release the details of the Maranello outfit's secret agreement with the FIA, following last year's engine legality saga.
But now Ferrari boss Mattia Binotto claims the other engine manufacturers in F1 also suffered similar performance drops as a result of the clarified rules.
"I don't think it's just us," he said. "Looking at the power output of this season, many others - most of the manufacturers - somehow had to adapt themselves."
On the face of it, that would appear a dubious claim, as the Mercedes-powered Racing Point of Lance Stroll is a full 10kph faster in a straight line than the works Ferraris on the short straight in Hungary.
Wolff, who described Binotto's account as a "total bull**it" story", confirms that while Ferrari's power went down from 2019 to 2020, Mercedes' went up.
"First of all, those directives only stated what was already part of the regulations," he said. "That limited one competitor at most."
Wolff added that Ferrari's immense performance prior to the FIA clarifications meant the designers at Mercedes had to work overtime in 2019.
"They almost forced us into burnout to counteract it, with the ironic result that we have now taken a decent step with our engine," he said.
Pierre Gasly, who drives for Honda-powered Alpha Tauri, was asked by a reporter on Saturday if it is true that the other manufacturers also suffered as a result of the clarified rules.
He said of Ferrari: "I think last year they had an incredibly fast car, and now it's as fast as everyone else's."