I do think that Jessops is your problem. I had a similar issue when I lived in Sweden: prints and scans were a little soft and quite contrasty, it drove me mad for a while, I started questioning my lens, my technique and my film. But those same images that seemed so soft are now producing wonderfully sharp 10x8 prints in my darkroom. The problem was the scanning.
Originally Posted by cyberspider
Try another lab, it might have to be mail order but you need to find a good one before you can start working on your technique. Otherwise you'll never know if it's you or the lab that's to blame.