I thought pure dsl is a totally separate line hence they would install a new line..?
All he did was temporarily install a feedback device on my end, and then do whatever voodoo he did on the exchange side for 45min, as far as I know. I pitched when he arrived to make sure everyone was on the same page but had to go back to work.Maybe he did install a new line just used the existing pairs of copper in the existing line.
I don't think he did anything to the physical cable, maybe they did a few changes to methodology for the sake of expediency.