If the spine wear is noticeably uneven, don't you have to add more tape on the more worn portion to make it even with the less worn portion? I mean, if the heel portion of the spine has 0" wear, but the toe has 0.2" wear, then I think you would want to add tape only to the portion of the spine that has the wear, so as to "fill up" that 0.2" gap. Whereas, adding a uniform amount of tape across the entire spine does not eliminate the 0.2" gap.

Or am I missing something?