LEXUS likes to do things its own way, writes William Scholes. First, there's the commitment to hybrid drivetrains, which it championed long before their low CO2 emissions and associated tax benefits made them fashionable among business users.
Then there's the aversion to diesel. When you're trying to sell cars of the sort that appeal to business users, this is a bit like going into a fight with not one but both hands tied behind your back.
The sort of people who buy cars with BMW 3 Series, Audi A4 and Mercedes-Benz C-Class badges on their tailgates love diesel, and without a diesel of its own under the bonnet of the current IS saloon - the last generation was highly sought-after when Lexus did deign to give it a diesel - its never quite caught on in quite the way that the basic car deserves.
This is a shame. The IS is crisply styled and beautifully built and while the petrol-and-electric hybrid drivetrain of the IS300h is beautifully relaxed, I've always felt it had the potential to raise the pulse of enthusiastic drivers.
The chief obstacle to exploiting the potential of the IS as a car to appeal more to the heart than the head is Lexus's continued use of a continuously variable transmission as opposed to a proper automatic gearbox or a dual-clutch effort.
Now, CVTs can be made to cooperate with the whims of the performance-minded driver - Subaru is rather good at this, for example - but the Lexus unit is defiantly obstructive.
Depress the throttle for a bit of get-up-and-go and the engine screams at the upper reaches of the rev range, and the associated whines and screeches mean you quickly get the hint, ease off and settle back into the IS300h's comfort zone - which is, it must be said, a very comfortable place indeed.
There used to be a non-hybrid IS250 model which met some of these problems by having a six-speed automatic gearbox but the 2.5-litre V6 engine, while as smooth as silk, lacked shove and was heavy on petrol and high on emissions.
The IS250 has been dropped in favour of a new IS200t model.
On paper, this promises to be the best IS yet because it pairs a modern 2.0-litre four-cylinder petrol turbo engine with an eight-speed automatic gearbox.
Sadly, it's an opportunity missed.
The engine apparently produces 241bhp, which is a very healthy output, but it somehow completely lacks in urgency, as if it simply couldn't be bothered.
Rivals have to include Audi's A4 with the 187bhp version of their own 2.0-litre turbo but despite giving away more than 50bhp, it actually feels brisker than the Lexus.
It means the Lexus feels slower than it ought to, which is a curious phenomenon.
Not as curious as the gearbox, though.
I had fervently hoped that this eight-speed unit would, as with the wave of a magic wand, transform the IS's transmission from CVT frog to automatic prince.
Not so; in fact, Lexus seem to have conjured up a gearbox that is actually even less pleasant to operate in spirited driving than the hybrid's CVT affair.
In fact, it's unpleasant almost all of the time, and isn't a patch on the rival transmissions found in an Audi A4 or BMW 3 Series.
It does share the Jaguar XE's odd hesitancy to get off the line, teasing you with its will-it-won't-it get off the line antics at junctions. This creates stressful moments joining roundabouts and such like.
The Lexus's transmission also liked to hunt around for what it thought was the correct ratio, which rather misses the point of an automatic gearbox.
According to Lexus, the gearbox can vary its shifts according to G-forces, dropping several ratios under hard braking and then holding a lower gear to help you accelerate out of a corner.
Despite several attempts, I didn't notice this, at least not to any great effect.
Taken together, the IS200t's curious gearbox and oddly lacklustre engine - which is also thirstier and produces more CO2 than key rivals' equivalent units - make this another head-scratcher of a Lexus.
The IS has so, so much to recommend it.
High points include distinctive styling that is attractively non-generic German, epic build quality, lovely steering, handling and body control, and delightful details such as the LCD rev counter that glides across the face of the instruments to reveal a digital information screen.
But it is hard to see where the IS200t fits in. Sure, it's £1,000 cheaper than the hybrid 300h but it's more expensive to run and doesn't offer a driving experience that is demonstrably superior.
Another opportunity missed, then; there's a proper driver's car in there somewhere...
:: AT A GLANCE
Lexus IS200t
Price: £31,495. As tested £35,490. Options included leather upholstery £2,000 and premium navigtion system £1,995
Engine and transmission: 2.0-litre four-cylinder petrol turbo, eight-speed automatic gearbox, rear-wheel-drive; 241bhp, 258lb/ft
Performance: Top speed 143mph, 0-62mph in 7.0 seconds
Fuel consumption: 39.2mpg (EU combined); 29.2mpg (real world)
CO2, road tax, benefit in kind: 167g/km - £300 in first year, then £210 annually - 30 per cent
Euro Ncap safety rating: Five stars (91/85/80/66)
