had a think about that, but single speed won't work on dual suspension without some sort of tensioner. the guys at batemans bay cycles offered to fit a tensioner so i could go out in the 50km, but with no spare hanger there was no way to fit it.
it can work, it will just depend on what is the best chain line u can get.
last year, i managed to mangle my rear derailleur just before the 1st creek crossing on the Andersons Firetrail. pulled out the multi tool, removed the mangled mech altogether. then used a chain breaker and removed the extra links as i would need to climb out in granny gear anyway. i always carry a spare power link in my pack.
the climbs were easy, just got the shits once i was on the flats and my legs were like egg beaters, but i wasn't going anywhere .
did manage to make it back to car though
edit: sorry . just realised i was also able to lock out my rear shock. then it was do-able .