Query about sentence in Notation Reference

[James Lowe]

Hello,

While scanning through NR 1.2.2 the last section I came across the line

> When a multi-measure rest immediately follows a @code{\partial}
> setting, resulting bar-check warnings may not be displayed.

I never like to see the words 'may not' without some kind of 
qualification in documentation - especially for things that help verify 
mistakes or problems, so I tried:

relative c' {
   \compressFullBarRests
   \partial 4 c
   R1*12
   a1 | a4 a a a a |
}

and I *do* get bar-check warnings.

So I did a bit more of a 'variation on the theme' and couldn't NOT get 
bar check warnings to appear.

Does anyone therefore know when I wouldn't get bar-check warnings 
displayed in this case?

I couldn't find an obvious tracker issue (I am assuming 'postponed' 
issues are still considered 'open' in regard to the search options of 
the tracker web pages), so wondered if this was incorrect or if not when 
the case is (for an example perhaps and possibly an @knownissue).

Thanks

James