Here we have two methods of Language (formatTimePeriod() and formatDuration()) whose names mean pretty much the same thing. When to choose one over the other should be documented.
From what I can tell, the former supports abbreviating units and two specific strategies to avoid showing unnecessary units, yet the latter allows fine-grained control over which units to use (though does not allow abbreviation). However, it's unclear whether there are contexts in which one would be appropriate yet the other would not.
Version: 1.24rc
Severity: normal