Sounds like he did the similar to me. Think – “straight double track, brakes off, what can go wrong…” then “Oh that’s a big drop, but speed is my friend…I’ll hang off the back” then “why am I upside down in a ditch, can I feel everything…yes, is anything crunching…no, OK to stand up…phew” 😀 and 😳
I’ll be treating double track with more respect from now on…