Well the good news is I feel way better and my check ups are mostly excellent, so the stuff is helping as far as I can tell.
The bad news is I'm not sure how to address the issue when applying for wwoof or helpx gigs around the country.
I'm old enough to feel furtive about the stuff, though I have my Dr's blessing and encouragement, it still feels weird to be open about it.
I cannot speak for many people but I would not want MJ of any sort used on my property. I say that because I know how it is treated around here (even though we are right next door to CO). I'd also not want people using MJ and then being around equipment that could lead to injury. Working for lawyers makes me super paranoid! I simply would not want to be held liable for any possible drug or alcohol related incidents.
I have not managed a similar issue, and we don't do the WWOOFer thing thing currently on our ranch, but if I did and someone were applying, assuming all the legalities were in order in my state and such, I'd be cool with it as long as they made it clear it was for actual medical purposes and they generally seemed like a reliable person. I think if you are willing to disclose why you are using it and maybe even include documentation from your doctor (if that doesn't feel too intrusive to you or raise your hackles) it would probably go a long way. Also, I don't know how to put this delicately, but if you don't just generally seem like a lazy pothead, it will probably help. I would note that I have no problem with adults choosing to smoke for whatever reason, and I strongly feel that people who get medical/pain relief benefit should be able to do so, but from what I've observed 1) a large number of people who just like to smoke use the medical thing as an excuse for trivial reasons, and it would be good to make it clear you're not one of them and 2) getting WWOOFers and other "free spirits" to work consistently and competently on an actual farm/ranch is like herding cats even without weed in the mix, so if you can project a salt of the earth sort of demeanor to counter that it might help. Depends on your hosts, though--some are all for it themselves and won't care a whit.