nztim:Sounds like rubbish to me, back it the day lots of people had phone lines just to have a broadband connection and never actually had a phone plugged in, electrical signals from the NEAX wouldn't even be sent down the line unless the there was ringing, or the phone went off hook.
Not rubbish but wire connection methods have become more reliable. Insulation displacing connectors aren't as prone to oxidation as twisted joints. Previously a "wetting current" helped break down corrosion.