I've played around a bit with anchor placement and had a local buddy, truly a Hill style expert, tell me why most folks would do well with index to anchor. It lowers your draw hand at anchor point, obviously, but that really helps the archer to engage back muscles in the draw. A higher anchor tends to make it easy to lose the back tension on the draw, or make it difficult to engage. I was surprised at the difference.
I'm sure Howard could do whatever he wanted without a problem, but I definitely noticed a difference.