I'm sitting at a table, talking to the chief engineer for the new Lexus RC F – a gently spoken Japanese gentleman called Yukihiko Yaguchi – having just manhandled his new car around a private race track outside of New York.

And, to be honest, I've not had that great a time in the car.

In fact, I've been curiously disappointed by how cumbersome it had felt when trying to stop and change direction for, and remain composed in the middle of, this circuit's numerous corners.

And the problem is the car's weight. It simply feels too heavy to be genuinely agile – as most cars that nudge two tonnes when they have just a driver and fuel on board tend to on a circuit.

So I ask Yaguchi-san a simple question, hoping he'll respond with an equally simple answer. Why, I ask, does the new RC F weigh as much as it does? 

Because its chassis and body-shell are as stiff as it gets, replies Yaguchi-san via an interpreter. Also, he points out, there are more active safety features on the car than in just about any other rival. And in a nutshell, that's why the RC F weighs what it does.

So presumably your car's body-shell is quantifiably stiffer than the latest M3's, I ask, which weighs a full quarter-tonne less than the RC F?