Ok, I said I would post up on the hand brake progress.
First off I slackened the HB cable adjuster inside the car.
I got under the car with my spanners and released the hand brake cable from the offending caliper, I then got a spanner on the self adjuster spindle and proceeded to waggle it back and forth using some WD40, after a while it felt looser and I hooked up the cable again, replaced the gunk shield and sat in the car pumping the brake pedal, for what seemed like ages.
Periodic testing of the resistance on the HB showed that progress was being made. After I felt that my leg had dropped off, I tightened the adjuster and drove the car up the road to a steep hill (these are not in short supply in Plymouth!) and in a moment-of-truth style test stopped the car, applied the HB and took my foot gently of the footbrake...And the car stayed put!
Hurrah!
Fixed.
600 hand brake myth disspelled for evermore.
Untill the next time.