I have SP. I used to develop a slight but brand new symptom every two to three months. Despite hard exercise, I was worsening continuously up to the point that I could not climb down stairs without holding myself. I was also unable to walk distances greater than 500 meters. (1500 feet)
I started LDN last May and I can't find any new symptoms since. I haven't had any exercise for 4 months now because of hard work and lack of time, and I can climb down stairs with my hands in pockets. I can also walk until my legs hurt, over 2 kilometers. That is astonishing!
Well, there are some bad days, too, but they are much much better than the best days before starting LDN.
It does work for SP and the lucky people are a majority, about 70% (but it must be more). 70% is superior to the 25-30% of the CRABs. Trials are needed to find out why LDN works and why it doesn't so that everybody benefits.
If God created MS, Devil would create Rebif to treat it!