Hi Lawrie, the track is only as crisp as a crisp thing

where the flash has hit. If you look to the outsides of the flash coverage the track line is wavy. Also the top black & blue lines if you look carefully are merging although this is more difficult to see as they are both dark colours & highlights & bright colours stand out more.
I estimate (guestimate ?) that the rise & fall on these riders in this picture is approx 8 or 9 inches, one of the main aims of pursuit riders is smoothness, if you take the 1/4 sec exposure that would mean they would be bobbing up & down 8 inches or so 4 times every second & the GB coach would be having a blue fit with his legs up, if you look at a video of top pursuiters you will see once they get into their rythmn the only thing going up & down much are their legs & feet.
In days of olde before digital & photoshop creative sports snappers had to get it right in camera & had an arsenal of camera moving & lens zooming tricks they employed during slow exposures, holding the camera at 45 degrees so it looked like the subject was either flying downhill or racing up, turning the camera during exposure to get some strange final images & that old favourite (stand up & take a bow) the zoomburst, to name but a few.
Ed is right when he says 'shopping' editorial photo's is a big no-no (although I have seen this done fairly recently

) but I would stake my life this is 'in camera'
Stew.