Pulled this comment out from #69 so we could discuss separately and clarify either way.
Do we intend the aria-description value on an element to be able to be included in its description by a self-reference in the value of aria-describedby?
If so, that does not appear to be supported by the current definition of aria-describedby computation.
If not, we may want to make that constraint more clear. It would make the behavior of aria-describedby slightly different from the behavior of aria-labelledby.
Pulled this comment out from #69 so we could discuss separately and clarify either way.