Not quite sure I've got the solution to this one - but posting it to see what others think.

Conventional training and good airmanship when navigating along a feature such as a railway line or river is not to fly directly overhead the river/railway/etc but to keep it on your left hand side - about quarter/half a mile away.  Presumably this convention came about because (1) it reduces the risk of a head-on collision with someone navigating along the feature in the opposite direction and (2) it's generally easier to see a feature to the left of the aircraft if sat in the P1 seat.

I have an (as yet unsubstantiated) observation that increasingly people seem to be flying 'dot to dot'.  I speculate that they plot a route on Skydemon (and others) where it is easiest to click on VRPs, villages, airfields, etc  and then they fly along the magenta line.  We've inadvertently created GA airways, with everyone at 2000ft, but heading in both directions.

Aside from the safety issue of head-on collision, it's also a bit of an irritation if your village happens to be a VRP, and every other aircraft out of the nearby airfield flies directly overhead it, because their magenta line says so....  (whatever happened to navigate around villages, not overhead them?)

I wonder if there is scope for an 'off set my route' feature, that allows you to join all the dots whilst planning, and then shifts your route a mile to the right of most VRPs, and 2 miles to the right of any aerodrome waypoints (i.e. clear of the ATZ).