Nikolas Tombazis has denied Mercedes did anything wrong as Formula 1 prepares a key engine rule tweak for June.
The FIA will begin measuring compression ratios both hot and at room temperature, closing a grey area that had sparked controversy before the season.
"It’s a topic that’s been blown out of proportion," Tombazis told Corriere della Sera.
"I don’t think it deserved even a cent of the attention it’s received. We never believed anyone was trying to cheat."
The issue centred on teams exploring ways to optimise compression at different temperatures.
"Some decisions had attempted to modify the compression ratio at more favourable temperatures, and they were legal," he explained.
Tombazis said the FIA acted to prevent an escalation.
"We made some decisions at the end of February to ensure that the entire F1 field didn’t engage in a race to find exotic materials or solutions that would go against the spirit of the sport."
"It’s something we often do when faced with certain situations - we don’t ban them, but we prevent them from dragging on too long."
He rejected suggestions Mercedes had crossed a line.
"I don’t accept criticism that someone was trying to cheat, even if the solutions were perhaps not intended by the regulations."