[Alex P]

No worries,
That was one question answered as I would also expect diesel leaking outside if there was an air leak in the filter housing or pipework from the filter housing to engine drawing air in to the system and there isn't any diesel leak anywhere.
As for the compression test, is the test in Vida sufficient or a good old fashion compression test with injectors removed?? I'm pretty sure the engine mechanically is sound as it's been pampered by me for the last 50k miles and 5 years of owning it with frequent oil changes along with these engines are bombproof?? I know the car inside out and this is the first time it's ever missed a beat and I would doubt it but obviously can't rule it out totally.
The hesitation seems to have calmed down a little today as it was driveable but maybe I've learned to drive around the problem area now so it seems better. The misfire is just the same as when the TC does a hard cut from 1st to 2nd gear on heavy accelleration with wheelspin.

One thing that has played on my mind especially the problem is a little tricky to track down - about 2 years ago I'm pretty sure a silver paper cap fell off a bottle of millers fuel additive down the fuel filler and at the time I couldn't recover it so had to leave it to go down the neck, what would be the scenario inside the tank if debris like this entered the tank. Would the tank filter or baffles stop this ever being a problem?
Really clutching at straws here but still driving it just in case it actually logs some faults in VIDA that might lead to something more to go on.