But is this most puritanical of views fair? Okay, so the 911 Turbo cab does seem to pander to the Malibu Beach tastes of the uncommitted enthusiast, and does seem to be used as a penis extension more than most 911s, but surely the folks in Stuttgart wouldn't actually let a 911 out of their factory gates that couldn't also cut it as a 'proper' driver's car?
To find out, we took a 911 Turbo cab (in oi-look-at-me yellow and with the almost-an-auto PDK gearbox, no less) along a 2000-year-old test route.
After all, the Romans were famous for the straightness of their roads, and the Fosse Way, in its original Romano-British incarnation, never deviated from a direct line between its extremities by more than six miles.
Despite how it may appear on your road atlas, however, the modern Fosse Way is far from an arrow-straight stretch of dull Tarmac. These days, the most southwesterly section of the original route has all but disappeared, while the north-east section between Leicester and Lincoln has become the dull and busy A46.
So you see, while an old Roman road might not seem like much of a test on paper, in reality it should be quite a challenge for the 911 Turbo cab and reveal whether or not the arguably 'least Porsche-ey' of all 911s can wear the badge on its nose with pride.
So instant is the 911's mid-range punch, in fact, that it's one of those cars where you only need open the throttle for a small part of the overtaking manoeuvre; unless you are really chancing it there's no need to do anything other than simply cruise past after an initial stab of the throttle.
The straights prove the pace of the 911's twin-turbo 3.8-litre flat six beyond all sane doubt - this is a car that can hit 62mph from rest in 3.5secs and, boy, does it feel like it. Keep your foot down and the nose of the car just hoovers up the road, the engine all breathy, roaring induction, with the characteristic boxer growl in the background.
The bumpier B-road Tarmac, however, reveals the first possible chink in the turbo's thus-far impeccable pukka Porsche credentials - the bumpier it gets and the faster you go, the more you notice a bit of wobble. It's forgiveable, but it is a first reminder that this is a less-than-hardcore Porsche.
The mild wobbles are helped, however, by the optional dynamic engine mounts - part of the £2743 sport chrono package, although stick the 'Sport Plus' button on and the suspension will firm up sufficently to bring the wobbles back (keep that switch for the track only, would be our advice).
As the Fosse Way moves into Warwickshire it gets positively twisty (in parts), providing an opportunity to test the 911's cornering behaviour. As is to be expected of 911 Turbos, there's a good deal less adjustability than in two-wheel-drive 911s, but there are epic levels of grip, and the PDK gearbox is improved almost immeasurably by the simple switch of the infernal standard wheel-mounted rocker switches for column-mounted paddle shifters (a £283 option) - it's now both more intuitive and involving.
The answer arrives as the sun comes out and I find myself cruising through the countryside with the top down and full of the joys of an impending spring - it doesn't matter. Just for the record, I reckon the Turbo cab does involve the driver (just) enough to satisfy hardcore Porsche purists, but that's not the point.
The committed Porsche fans won't buy one of these, because they'll go for a simple Carrera, or a GT3, or even a GT3 RS instead. But if you want a car that's fast enough to blow away the most sticky of cobwebs and yet that can also allow you to experience the simple pleasures of open-top motoring, you could do a lot worse than a 911 Turbo cab.