Sandy, Bob Godfrey used absolutely basic techniques in the old days. Roobarb and Custard animation was so rudimentary, he used the "boil" method, where matching the line and colour didn't matter, and after the pics were all held for a few frames only under camera, than played back in a stream, the animation looked like it "boiled" on screen. He used magic marker to colour in the characters, and worked so fast, (due to time constraints) he could spend NO time on finesse. It was a lot of fun and lent itself perfectly to kids TV.
I worked with him (as an unpaid intern) on the famous TRIO ads, where he was asked to recreate that method, but the directions he had to comply with from the ad agency meant he had to take a lot more time and trouble to fake what was originally a very simple process. Therefore the simply-rendered characters had to be cut out and mounted on see-through cel so that they could be used over painted backgrounds. Bob was paid a shedload of money to do it, he couldn't believe the budget, it went a great way to paying for his Covent Garden studio (a tall, narrow converted warehouse).
The guy who rented out the office underneath was the Guardian's Steve Bell, someone I was lucky enough to spend some time with. He was working on a spoof animation of Robert Maxwell at the time. I was given the great privilege of drawing some stuff for that. I'm not a huge fan of Steve's Guardian work I am sorry to say, but he is a great fella to talk to. He is, after all is said and done, Steve Bell.
