I got a really large gap between single and multithreaded results, which to me shows it is all about the testing methodology’s inadequacy - it’s measuring their chosen protocol’s performance, not the link. Having said that, I’m not so surprised as I would think there is a chance that their servers are seeing out-of-order packet arrival times due to my four pipes and maybe that is freaking their TCP implementation out?
If I had had any wit at all, I would have posted a link to the specific correct page, but the url looked somehow weird to me, whatever that means, and I somehow got it into my head that it was one of the personal or per-session calculated ones, urls that cannot successfully be given to someone else as they are meaningless outside the context of one session or when away from the original user. Duh.
My latest test results:
Notice the huge variation in the upstream. These are both runs of the ‘special’ test, so I was wrong earlier: the difference that I saw originally is just between one run and the next, not due to the difference between types of tests. Regarding the upload: one is a bit exaggerated and the other is way, way too low. The downstream numbers are about right. One modem is swapped out at the moment for a spare DLink DSL-320B-Z1 instead of the usual ZyXEL VMG 1312-B10A and the downstream sync rate is about 380k lower than normal, so this means that the downstream test result shown here is expected to be down by about 320kbps.