Lately, I feel like I have really been using the leg yield as a tool... not just a movement.
For example, Barb had me leg yield along the wall (at your standard 35 degree angle) at the canter to engage the horse's hind end and push them more honestly into the other rein (you know, the one that isn't holding 300 pounds of fat horse up!). Trust me, it did the trick and is the ONLY thing I can imagine that would.
We then went on to alternating between the canter half pass, to the leg yield in the same direction (half pass left, change bend and leg yield left). Really got the jumping from behind without having the chance to get stuck on either forehand.
In another example, I had a horse that was just not responding to my my leg aids or bending to the right. As a result, he was just hanging on that inside when I was on the right lead. To fix it, I leg yielded him along the wall, half circled back and leg yielded along the wall in the other direction. Think of it as a modified version of that ice cream cone shape we all love riding in tests.
By the end of leg yield to other bend to leg yield to other bend, that horse was like butter... butta!
Needless to say, the leg yield is the hot sauce of my rides... when applied properly and only when necessary, it really does the trick!