Re: duplicate dynamics on same staff

[vicente]

>> if the dynamics are the same, it's better to write them just once. thus
>> you:
>> 1) save typing
>>
> Yes, if I were just starting, I would save typing. This time I didn't
> discover this problem until I already had it done the other way, so it's
> just going to be extra work. Yeah, I know I'm whining about the hour it's
> going to take,

then you can just prevent the dynamics printing on one voice:

\version "2.12.3"
<<
  \new Voice = "A" \with {
    \remove "New_dynamic_engraver"
     % it could be "Dynamic_engraver" in 2.13, I'm not sure
  }

  \relative c'' {
      \voiceOne
      a\f b\> c d\p
  } \\
  \new Voice = "B" \relative c' {
      \voiceTwo
      c\f d\> e f\p
  }
>>

>>> if Lilypond can see that one of these
>>> things needs to be moved, how hard  would it be to have it determine
>>> that they are identical and just not print one of them?
[...]
>> 2) help lilypond so it doesn't need to waste time guessing obvious
>> things and it can concentrate on the big stuff  :)

I actually don't know if what you requested is possible at all with Lily.
I might be just speaking too much...

greetings,

Vicente