I spoke at length to my neurologist about the odd sensation of my bending my head forward that I wrote about in this post. and feeling numbness go does my spine and the resulting spasticity in my legs and how that not being my head forward makes the spasticity almost entirely go away.
Apparently it has a name: Lhermitte's Sign named after a French guy who wrote about the phenomena. While it's nice that other people experience it (1/3 of people with MS feel it.) There's not a lot known about what causes it. Turns out my theory about the lesion in my neck causing it may not be that far off at all. My Dr. explained that the spine is very mobile and it could easily be running over the lesion when my head bends forward.
Oh and that 4th symptom that I occasionally deal with (but very rarely now) that I couldn't think of when I wrote the original post is: fatigue. I'll edit the post.