ali corrodes awful. copper doesnt - just bad joints. on the very best ali joints i have noticed the insulation peels off very easily, also ali doesnt like being bent as much. Once an ali joint gets wet it is finished, unless there is enough slack to cut back 60cm (rare) and the engineer is allocated enough time to repair (never), then a simple recrimp will result in unintentional hr dis faults, with almost every subsequent repair or interventiin in the joint knocking other lines off.
performace wise over 3km of line on my local cab a change from 100% ali run to 60% ali run gives an extra 2meg on adsl 2.
the rule of thumb when taking measurements on ali was to add 20% onto the result - i.e. a line measures 100M for copper line tester is actually only 80M long if made of ali.

if your estate is 5 years old you d side cable should be .5 copper in duct , so good news.

As for you e side who knows !

Cool story bro!

my question is how did you do what seems to be the impossible for a normal customer?

Get your cabling upgraded to higher quality,

In reply to a post by Chrysalis:

my question is how did you do what seems to be the impossible for a normal customer?

Get your cabling upgraded to higher quality,

DIY

this can be done on a BB boost job.

Not impossible, but would say rare.

BT does more repair/uplift work than I think many would believe, the reason it goes unnoticed is the vast majority don't know anything about their broadband quality, or were confused by what their ISP told them,