On paper the Jaguar XJ Supersport sounds like the ideal car for those in the chauffeuring profession. After all, if it’s good enough for ferrying around the Prime Minister or James Bond’s gaffer then it should be good enough for most Captains of Industry.

Your VIP can climb into the generously proportioned rear of the XJ, the soft close doors making their life even easier as they get comfortable. Reclining in the soft leather of the rear seats is a real pleasure and in this long wheelbase version there’s enough space to stretch out and relax. As they do so they can choose to listen to the distant rumble of eight cylinders transporting them to their next business meeting or they can revel in the sounds from the Meridian sound system with TV screens built into the front headrests.

Meanwhile, up front, you’re enjoying the massage function of the soft perforated leather seats that can be either cooled or heated. Your job is made easier by the smooth eight-speed ZF automatic gearbox and the effortless pull of the 5.0-litre 510PS engine.

There is, however, a catch. While you have your precious cargo on board you’re going to have to exercise restraint. Pressing firmly on the loud pedal is a no-no as it could disturb the peace in the back, so you’ll have to make do with gently flexing your right ankle until you’ve offloaded your passengers.

Then you can play. And you will want to play. That V8 rumble tempts you into treating the XJ like a proper sports car and make full use of its prodigious power. The responses from the steering and chassis fool you into thinking this is a smaller car but don’t let it kid you. The XJ is very long and very wide and on narrow roads you may find yourself subconsciously holding your breath as you squeeze past oncoming cars. If you’re going to make the most of that engine and exhaust note you need wide tarmac.

Careful you don’t have too much fun though. If your employer sees the grin on your face and realises how much you enjoy driving their XJ Supersport they may decide they want to try it for themselves. Then it’s Game Over, because they won’t want to be driven anymore. They’ll want to keep that V8 all to themselves and that’ll mean you’re demoted to valet duty instead.

So on paper the XJ Supersport might sound fantastic if you’re doing all the driving but in reality you run a risk of losing your cushy role behind the wheel. Perhaps it’d be better to suggest that your employer buys the diesel XJ instead.