galvonager, this app uses exactly the same data the previous picture is based on, but with its own kind of interpolation, which may or may not be a better approximation of the real track.
You're saying that the only data we have are the data points (marked on the first image as such), and everything else is interpolation? That's quite possible. Still, the helicopter behavior makes the Passur track more believable to me.
Does more complete data exist at all anywhere? (The data points on the first picture, being the presumed basis for mine, are from the transponder, right?)