I recently traded in my Mk 1 (2003) Focus 1.8TDCi. As someone has already pointed out, the stalling is deliberate if engine speed drops too low, to protect the DMF. The car was also fitted with a very low first gear, aparently to facilitate pulling away without stalling. The clutch was quite sudden, too, which didn't help, but I've not driven a later model 1.8 TDCi.

The car still needed some revs to pull away, though, and surely 1400rpm is not an excessive engine speed to use in order to pull away cleanly? Bear in mind that turbodiesels tend to have lower compression ratios that naturally-aspirated diesels and so will develop less torque at very low revs, before the turbo starts to boost, and are thus easier to stall.

The remap I had was certainly worthwhile, though, as it enabled the turbo to kick in more responsively on part-throttle, making the car feel much livelier to drive, as well as having more ultimate power. Economy improved by 2-3mpg at the same time. I was informed that the fairly basic ECU used on the 1.8 motor meant that the remap was not detectable, even by Ford dealerships, though I'm not sure if that holds for the later models. The remapping company told me they were actually remapping new Fords in dealerships, as customers had complained about the power delivery of later model diesels, which had been 'adjusted' for emissions reasons...