I've made the keys equal and unequal. I do like using unequal because it it easier to come out with appropriate size strips. (For example, if they were all to finish at 2" and you just have the need for 1 1/2" at the end, it shows up). I do them various widths and then miter the corners, knowing that the seams don't have to match. It is still quite effective. I'll try to insert a picture. This is a Double Disappearing Nine Patch.
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