You know, there is nothing to stop other companies building and installing their own infrastructure within their own exchange buildings, ducts, joints, cabinets, distribution points, cables etc.

It is foolish and narrow-minded to assume that infinite speeds can be achieved over copper. Fibre is coming in, slowly but will be totally useless until 21CN roll-out is active. Current fibre in the network is unusable for broadband and upgrading the line card costs £30,000 per card - there are quite a lot and it is a poor investment when 21CN is just around the corner.