Jof,
We were (or rather Milo was) talking about "backhaul networks" - C&W sold off the Bulldog Customer base, not any of the network, and Plusnet may have been an early adopter of QoS technology, but that isn't a backhaul network.
And while CWW did go through some troubling times, it was not a "collapse". By that measure, Apple, IBM and BT among many, many more have "collapsed"!
SD