Seeing as BA staff are unable and/or unwilling to enforce current boarding rules, why would anyone expect this to be any different? And doesn't the whole idea of introducing a new system that will affect every departure to every destination run somewhat contrary to BA's current race to the bottom in terms of service standards?

To my mind, there is nothing wrong with the current system which was clearly intended to make boarding faster and more comfortable for everyone. The fact that it seems to be rarely, if ever, enforced means pretty much every flight has a 30-minute line of stationary passengers queuing along the aisle of each plane, because people are trying to get to the back of the plane whilst others are seated near the front and are blocking the aisle whilst stowing their luggage.

I really don't see the point in creating endless boarding groups to recognise every status and cabin combination. Is it really necessary to have more than the following simple categorisation:

Premium cabin passengers can board at their leisure
1. Special assistance/families
2. Gold/Emerald status only
3. Everyone else, ideally in blocks of 10 rows each

The current system isn't broken, it's simply not being followed. Why try to replace instead of fixing? It just requires 2 staff members to say 'no' to a bunch of self-important chancers.