bogus (and or missing) error messages

[Hugh Myers]

Often I get the following pattern--- say I'm working on bar 59 and
make a mistake. After the compilation process, the error message
refers to bar 22! Given that I'm working in relative mode, I'm
confused as to how code that was moments before correct is now in
error?

Another pattern I see frequently is the over printing of the 'Music
engraving by LilyPond 2.13.7—www.lilypond.org' when it is mistakenly
placed at the bottom of the first page because the second page has be
wrongly compressed into the first page--- lots wrong, no errors---
why?

--hsm
p.s. all of this goes away when I find the actual error and correct
it. Since by experience I know it is in the current bar, I'm just
wondering where the 'NOISE' is coming from...