By accident, I ran across a court order (see 337 F.3d at 1024) that the following footnote be added to an earlier opinion:
We do not confront here a claim of failure to exercise discretion or manifest injustice.
No-one will be actually confused by this, of course; but at least on first reading, it might strike people the wrong way, as "We do not confront here a claim of failure to exercise (discretion or manifest injustice)" (borrowing the mathematical and computer language meaning of parentheses). The very absurdity of "failure to exercise ... manifest injustice" will prevent actual confusion, but it might cause an odd reaction at first. It might have been better to say,
We do not confront here a claim of failure to exercise discretion or of manifest injustice.
Alternatively, if the order of the options wasn't rhetorically significant, the court could have said,
We do not confront here a claim of manifest injustice or failure to exercise discretion.
But this too might be a bit ambiguous (though perhaps not relevantly so), since it might be interpreted either as
We do not confront here a claim of (manifest injustice or failure to exercise discretion).
We do not confront here (a claim of manifest injustice) or (failure to exercise discretion).