Re: How fast could BT Infinity go in the long term?
There are people who already have maximum attainable rates of over 100Mb.
With a technology called vectoring this will be attainable by considerably more people.
Using the current settings, 17a, with vectoring, theoretically Infinity could do 120Mb Symmetrically, or have 246Mb split between upstream and downstream.
If BT were to increase the bandwidth to profile 30a, which requires regulatory approval, the bandwidth to split between upstream and downstream becomes 417Mb.
Please note that this is with a single copper pair. Nearly all homes have more than one pair, and with 2 physical pairs and a technology called 'phantom' DSL over 750Mb has been achieved at 500m from the cabinet.
So, for the majority of people, if you say 500Mb - 750Mb you're about there.