[roughbeast]

It has been said here that even if the link between the larger boxes you identified and the smaller boxes was fibre we wouldn't get a better service. As it stands Virgin architecture is fibre to the node, coax to the street box and then a shared coax to the premises. This is FTTN. Only if fibre is within 300m from the premises can it be referred to as FTTC.

The potential bottle neck with VM is the shared coax from the small street box to the premises. It only works because it depends upon most people on the coax not needing full capacity most of the time. Some people in congested well-subscribed areas notice a small drop in speed during peak times. As has been pointed out, those areas with oversubscribed street boxes do suffer less than the advertised speed quite a lot and get a lot of jitter.