I also have read the same thing. I have RA as well, and I have Gluten intolerance (although not confirmed via biopsy). Eliminating gluten from diet has eliminated my GI symptoms, but it hasn't really done much for my joints. My rheumy, though, I think was hoping that it would. Everything is connected, and diet is key, so it would make sense that your diet would increase or decrease inflammation, depending on what you ate.
Perhaps if I go gluten - free for a few months (I cheat too much now) in a row I might see some results with my joints.