I came across this post in April, 2012. Just wondering if you still follow this site. I have similar problems (tight hamstrings for 20 years, and knotted calves / painful feet for 2 years). I've seen massage therapists, doctors, PT's, and a chiropractor. A rheumatologist had me on methotrexate for a while. Nothing has worked.

I just figured out the MPS thing and believe that injections might be the way for me. Did you have any luck?