After a scan, I was diagnosed with the IT syndrome too. I rested and did
these streches for a while, but the terrible knee pain (and swelling) never dissapeared.
After months of struggeling, I visited an osteopath. She felt up my body for nearly an hour, asked tons of questions, made me do dozens of streching exercises and concluded that my quads got biggger as a result of my training. This really surprised me, because I'm a really skinny climber-type guy. My legs are really thin and don't seem muscular at all, so I did'nt believe her at first. She explained that my knee coluld'nt move the way it should because of the quad-muscles exercising pressure on the joint.
The osteopath thold my I schould strech my quads in tha classical way (lift your leg back and pull the ankle till you feel it in the quads). I did this during a couple of weeks and the knee pain and swelling slowly dissapeared and I have ridden the best season in my life since.
Just so you know you can get easily misdiagnosed sometimes and have to visit several doctors before you find a solution.