I am well aware of modern technology, as I thought I made clear.
I do not doubt that, Bob! My point was that the uses for extension sockets are waning and in many cases it is best to disconnect them or fit a faceplate filter.
My brother and sister in law have awful ADSL2+ where they live. FTTC is available, but they are so far from the cabinet that they are unlikely to get a significant speed increase.
Their house has an old LJU1/1A or LJU2/1A master mounted on the skirting board (I can't remember whether it is the 55 x 55mm LJU1 or the 68 x 68mm LJU2 offhand, and it's 250 miles from here so I can't easily check). From there, there was an internal twisted pair cable running to an IDC block terminal under the stairs, from where star wired extensions run all over the house using a mix of good quality twisted pair and total rubbish flat cable. It's a 1970s house, with the sort of setup Chrysalis describes with sockets in almost every room.
If they had an NTE5, I would have fitted a faceplate filter. As their Home Hub 4 and cordless base station are both connected to the master and their Sky box only has Wi-Fi connectivity, I chose to disconnect the twisted pair cable running to the extensions from the back of the master. After pulling the wires out of the blocks using the hook on an IDC tool, I cut off the damaged tips of the wires and wound the remainder of the wires neatly round the cable in the back of the box.
Sadly, this resulted in slightly better speed but did nothing for the reliability problems they had failed to mention before I started troubleshooting their wiring. It turns out that they have dreadful problems with intermittent noise on voice calls and their router disconnecting, which suggests an unresolved bad joint somewhere. Unfortunately, they refuse to pursue it with their ISP, which is a shame as I think they would have much more reliable service if the fault is fixed. They may also finish up with an NTE5 in place of their existing master. At least if they pursue it now, there is no chance of their internal wiring being blamed as it has been disconnected!