I forgot to touch on brace height, which was what your question was about. With a 28" draw I would be more inclined to stay around 7" brace height. With my sub 27" draw I have shot as low as 5 3/4", but about 6 1/4" works much better for forgiveness. 7" works even better. So what little I gained in speed was offset with less forgiveness.
There's a lot of debate about forgiveness and how to get it. It's never one thing such as brace height. It's a combination of several things such as brace height, a2a of the bow and size of the cam(s), riser geometry, rest type, balance of the bow, and even how well the bow fits your stature. Even too much draw weight enters into it. It's a lot of thing all balled into a complete system.
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