I think the prime rule we lived by in Karting would apply to MX as well.
The onus was always on the passer to pass safely!
BUT the slower person had to hold their line and not wander all over the place.
Probably a little harder to do on a trail but if the parents taught their kids to try not to wander all over the place and make erratic changes in direction there would at least be some predictability for the passing rider to SLOW down and then pass safely.
In saying the above I have noticed that the very unregulated atmosphere of the Enduro and MX world (as you can't have a flag marshall with a blue passing flag in the middle of a forest can you!) is made really really good by the helpful interaction between most riders. Riders helping strangers and kids they don't know whenever there is a problem! If it wasn't for this good general attitude between most riders there would be significantly more accidents and injuries.
So I think we just need to have a bit of patience in most situations (after all we where all there in the beginning weren't We!) especially when there's no finish line or chequered flag at the end of the ride!!!
On a Motorcycle you're penetrating distance, right along with the machine!! In a car you're just a spectator, the windshields like a TV!!
'Life's Journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out! Shouting, ' Holy sh!t... What a Ride!! '
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