I *think* I had this yesterday trying to escape from London. Was in a lot of traffic around Tower Bridge and the crap hole that is Elephant and Castle. A couple of start offs seemed really sluggish; caught me by surprise. I'm pretty sure it was with very light throttle though.

Thanks for the replies everyone. Think I'll keep an eye it and post again if I find out anymore about it. Cheers!

Quick update on this. After sitting in traffic for 40 mins and creeping forward a few feet at a time, the car wouldn't move at all. I somehow managed to park up and left it overnight, when it was fine. Enough's enough; time to get it sorted....

I took it to the Land Rover Supermarket in Speke, Liverpool. They couldn't find any error codes on the diagnostic test, nor could they replicate the issue on a lengthy test drive. The chap said it definitely wasn't the gearbox as the issue would occur on every gear change. The only thing he could suggest was to change the fuel filter and give it a Forte Diesel Treatment as it was possible that fuel filter was clogged with gunk, and stopping fuel from getting through preventing the torque converter from engaging.

It's only been a week, but it appears to have done the trick! I've been stuck in traffic edging slowly forward a few times (you've gotta love the M62 during rush hour traffic: NOT!), and there's not been any recurrence of the issue. I'm gonna keep an eye on it, and will update this thread.

Thanks all!