I think due to the fact that since the beginning of the rollout they have been surprised at how many Homehubs and ECI modems weren't compatible. Then theres also the issue of the ECI cabs which dont appear to be able to do upstream either. Then choosing the most sensible path is to keep g.inp switched off for the upstream. SINET has always said that upstream is optional. They tried it and it caused too many issues for too many people so it makes sense that they dont apply it plus this way then its standardised for all and more compatible across all platforms.
The MkI system was a mess and caused large degredations in service so there was no way they could continue with the way things were. I think BT arent alone in this, when searching I found another foreign ISP who appeared to be having similar issues too. Cant recall who it was now, but the link is on these forums somewhere. Italy I think.
I seriously dont think your problem is anything to do with g.inp.... and if it is a fault materialising then regardless if you had g.inp or not before, then the line would still likely have further DLM intervention applied.
