Back in the mid 80s when I was young, impetous and didn't know any better, myself and 2 mates did a 3 day ride along the SDW. On both nights, we just pitched our tent a few feet away from the main path. No-one said anything to us except friendly greetings.
Perhaps people are less tolerant 25 years on, but I would have thought that as long as you're discreet, you won't have any problems.
gavin