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?

Not sure, replies Yaguchi, because we don't know how stiff the BMW is, but we know our car is very stiff indeed.

Which leaves me feeling a bit baffled if I'm honest. How can Lexus claim that the RC F is stiffer than the competition if it doesn't know how stiff an M3 is?

And does the RC F really need to be so festooned with (and therefore burdened by) safety features if, as Lexus claims, it's meant to be one of the most exciting cars to drive on a track in its class?

Don't get me wrong, the RC F is a terrific road car, one that's as rapid as it is refined; a machine whose on-road personality is pretty much defined by its delicious atmospheric V8 engine. Which makes it refreshingly old-school in this day and age, and therefore right up my avenue.

But when Lexus tries to convince us that it has built a car that's as sharp to drive on a track as it is on the road – and is therefore a competitor to the M3 in any dynamic scenario – that's when the rhetoric becomes harder to believe. Because track cars, really good track cars, should never weigh the thick end of two tonnes.

And, no, I'm still not entirely sure why it weighs as much as it does, either, although believe me I did try to find out.

Maybe the metal they use in Japan is simply thicker than the stuff they use in Munich nowadays. Or (whisper this) maybe Lexus has dropped the eight ball in this particular instance in its unceasing quest for safety and refinement. 

Either way, the RC F weighs a good 200kg more than it should, which means it's been given the worst possible start in life as a driver's car. Given how good the rest of it is, that's a real shame if you ask me.

Read Autocar's first drive of the Lexus RC F