The BCS Have Funny Ideas in General
On paper a lot of the BCS grades look fairly sensible, but in practice they have some very odd ideas.
They use a scoring system for different grades of membership where you need 50 points for the standard member grade. You get 50 points for a Computer Science BSc, 20 points for a BSc in any other field, 10 points for any MSc, and 10 points for every year you work in IT. In theory this sounds reasonably good, but in practice an ex-colleague of mine has been subjected to the following decisions from the BCS:
1) An MMath (four year maths degree consisting of all the course of a BSc in maths plus an extra year) only counts for 10 points,not 20 as it's a Masters, not a BSc. This means that, as he has 3.5 years of experience working in IT he's not yet entitled to full membership.
2) He then went on to do an MSc in Computer Science that normally requires a BSc in Computer Science first, but was allowed to take it without due to having a maths degree and experience working as a programmer. He got a distinction, but was told that he still can't be a full member because you can't count two Masters degrees towards the points, so he still only has 40.
3) After finishing the MSc he started on a PhD. The BCS informed him that they don't count PhD research (or the teaching and demonstrating undertaken during it) as work, but they will "most likely" award 10 points for the completion of the PhD. He's done well enough at teaching and demonstrating that he works on a variety of modules on both the BSc and MSc courses, and is trusted to have a thorough knowledge of the subject.
So, he teaches on a course that if he'd passed it would entitle him to full BCS membership, and he teaches on a course where most of the students either have full BCS membership or are entitled to it, but he still isn't considered good enough by the BCS to hold it himself.