The engineer that responded seemed very thorough, and fixed the issue with the one leg, and also identified and fixed a fault on the other as well. He was down a couple of man holes to do this, and had to get another guy to help him who had kit to lift "heavy lids".
Now, the phone is working fine, but my previously solid 80Mb max attainable, now swings between 66Mb and 80Mb. A difference of 14Mb!
There doesn't appear to be any correlation with time or weather. DLM has me profiled at 66Mb, and the SNRM swings between 3db and 9db.
Any clue what could have happened. Is it worth reporting it to my ISP?
ZeN Unlimited Fibre 2