I thought it was the other guys (naturally) but it happens so consistently I think it must be me.
Cons track just fine, nice and smooth, at anything down to d400. When I get to d200, I get a gigantic back-and-forth warp: con backs up, then zooms away again. Sometimes it does this twice.
Last time it happened, the warp took my right through the con - collision, unhappiness, etc.
Anyone have any ideas? I run a Dell Latitude D610 (yeah, yeah) over ADSL. Ping's generally around 220 from here in Australia.