Its easy for different issues to be wrongly bundled together and Brandon is spot on that the standard diags need to be followed before they are added to his open investigation. I always thought their would be more than there is currently but as we have both said before there may be many many more out there that don't know they have an issue or have not been migrated yet.
If it transpires what I'm seeing is as a result of GEA migration and were typical it's not difficult to see why folk wouldn't notice.
I'm on a 900mbps service and with my equipment I am still getting very close to that to some locations. Even the ones I'm not getting close to (including Zen's own server) I'm still getting over 500mbps.
So if that were typical; you might believe that you end up with no issues observed for many people, and then of the ones who have a 900mbps service, how many would notice that certain speedtest servers were not achieving such high throughput?
Maybe there is some other compounding factor for those that have such a poor result. Eg perhaps they are in an area with strong takeup of FTTP and so they're looking at one issue layered on top of another issue. I'm lucky that I think at the moment I might be one of only 2 places hooked up to our PON, takeup hasn't been high in the City Centre here in Norwich as there is very good speed via FTTC (most people I speak to get close to profile limit) and we've also had Virgin available for years.