I read that when Mercedes-AMG boss Tobias Moers heard the next C63 would need to adopt a hybrid four-cylinder engine, so that Mercedes could meet its CO2 emissions targets, he walked out of the meeting. And it wasn’t to go and buy celebratory bunting.

Moers likes multi-cylinder engines – making engines is what AMG started life doing, after all – and thinks V8s, as fitted to the C63 at the moment, are the heart of the company.

But the rules are the rules: big car makers need to find a way for their cars to emit an average of 95g/km of CO2 in 2021, phasing down to 81g/km by 2025 and 59g/km by the end of the next decade. There are minor complications based on weight and how many cars a company makes, but that’s the short of it. And if they don’t comply, they pay the EU money on every car they sell, for every g/km by which, on average, they miss the target.

Which means AMG isn’t the only one with grumpy engine enthusiasts. For companies on the breadline – which is most mainstream manufacturers, whose ambitions are a modest single-percentage-figure profit – finding 95 euros to pay per car, per g/km by which the whole fleet exceeds a target, is unthinkable. Increasing prices so customers pay it is no more palatable, either. And so they’ll meet it. Ask them and they’ll say: it’s not optional.