It won't hurt to try. I will recommend it to people looking for something to try, and I tell them to keep a pain diary for 6-10 weeks. If no change by week 10, it's not going to work. I would say some 30% have some relief - some of it is probably just placebo effect (some 20% of pain patients get relief from sugar pills in any clinical trial), some may be real. It's hard to take it bid or tid, though, so it's hard to say whether it's not effective for that patient, or they are simply non-compliant.
P.S. Glucosamine is generally shellfish origin, most common chondroitin origin is beef cartilage. I think I have seen a completely synthetic brand somewhere...