I know since I was diagnosed with IT band problems (and muscle strength incongruity) and went through physical therapy for it, I have seen so many posts about it here on the forum. I was reading Sweat Science this morning and an older article was posted about the merits of strength training vs. stretching to help ease this painful condition:

Strengthening, Not Stretching for IT Band Syndrome

This matches my experience - that the stretching exercises they had me do in the beginning helped a little, but when I started doing leg presses and leg lifts and using the resistance band (among other quadricep and hamstring strengthening exercises) that's when I saw real improvement with my knee and have since not had a problem with it.

Thought I'd share!