I thought this paragraph about the bars, from Pete Ramey's article, would interest some here:
Last year I quietly started experimenting with this in my own client horses and immediately found it was a significant improvement to my work. Shod horses come out of shoes much more comfortably if you leave a longer bar and backing off on bar trimming almost immediately and very dramatically increases the soundness and traction of most barefoot horses. The bars will almost always start to maintain their own height at the level of the sole or perhaps an 1/8th to 1/4 inch longer than the sole if you leave them alone. The less you trim the bars, the shorter they become! The flip-side is that the more routinely you trim the bars, the quicker they pop back and ’need’ to be trimmed again. Leaving a longer bar (and sole ridge around the frog) accelerates the process of achieving a deeply concaved sole by providing support to the internal structures and reducing sole wear. I already learned this lesson about the other parts of the foot years ago. The less I trimmed the sole, the deeper the solar concavity became. The less I shortened the foot, the shorter the foot became. The less I trimmed frogs, the more sound the horses were...... Every time I have learned to back off, my horses became more sound and the rehabilitation of pathologies accomplished more quickly. I was a just a bit slower in seeing the same truth about the bars. Now I’ve come to view them as a critically important weight-bearing structure and see that as with every other part of the foot, over-trimming them makes them grow too long; too fast.