Just a few things, aren't self installs just going to keep reducing your speed because of microfilters, or is this just on some connections?
Why are only some packages self install, why would I want an engineer for bt infinity 2, when self install is available for bt infinity 1? Really confused, thanks.
The new Master Socket effectively just includes its own microfilter - so there should be no difference betwen using individual microfilters at each socket (ADSL and Infinity self-install) compared to a new master socket.
The fact that BT (for now!) still have an engineer install for Infinity 2 is, I think, just an acknowledgement of the fact that the higher speeds are harder to achieve and that poor house wiring is likely to have more of an impact on these speeds (which people are paying more to buy!) than on Infinity 1
So a house that is estimated 80mb, but may only get 65mb on microfilters, would still get the full 40mb on bt infinity 1? Hence the self install not available for bt infinity 2.
I don't think the use of microfilters as such will cause any degredation over a new master socket (with built in microfilter) BUT the fact that the new master socket is always put directly on the incoming exchange line for the cleanest signal may well make a difference. Presumably, for self install, people are just going to connect the router to any extension they like (as with ADSL).
Even for ADSL broadband major improvments could often be made by comparing the master socket speed with that on an extension - and making improvements!
I do think that BT (and other ISPs offering FTTC self-install) are hoping that any slight wiring issues will cause less of an issue for 38Mb FTTC!