Background: There has been a massive local power cut, still in progress. I'm writing this while on my generator. I was asleep when my useless UPSs failed, ran out of energy and the wireless LAN went off while I was still asleep. When I woke up, the generator was turned on and the modems reconnected.
All the three modems have a substantially higher downstream sync rate now they're powered back up, around 200 kbps higher. And Andrews and Arnold's clueless.aa.net.uk server reports BRAS true delivery rates that have immediately gone up (no delay, like in the old days on 20CN where the rate increase notification would always be really late).
A speed test from speedof.me reports 7.4 Mbps combined downstream throughout, which is around ~1 Mbps higher than it has been of late. (The thinkbroadband speed checker reports no change and a much lower figure, so maybe the path to that server is a bit rubbish?)
I'll post the details of the modem info shortly when I feel a bit less groggy.
The point is, is this suddenly an experiment into the effect of the removal of all crosstalk. Presumably all the rest of my neighbours at the end of our five mile long copper bundle have their DSL modems off now, as I don't believe anyone else has a generator. So, apart from any possible locals very near the exchange who are in Broadford itself who have generators, this ought to be a measure of the situation with ADSL2 with all crosstalk removed.