It has nothing to do with the servers. HTC servers run under 10 percent capacity even on TT. Skuzzy says its has to do with your computer not being able to keep up with all the extra info coming through in the packets. SOme people with computers that are just good enough will have trouble on TT because they get a bit over taxed.
Actually I find that a bit odd. I never noticed such things back in the day when there was only one MA and at comparable player numbers. Some extra warping yes, hefty FR issues for sure, but never any phantom dots caused by enemy players opening their clipboardmap or completely weird friendly as well as enemy darbars & dots.
And my current machine is way better than two years ago, AMD 64 X2 4200+ with 2GB ram. But once we go 500+, I get all kinds of radar problems.