Understanding how \tag works in \relative pitched music

[Guy Stalnaker]

All,

Why is this output being created? I would expect to get exactly the same pitches on all three staffs, but since not, my expectations are obviously wrong.

%% SNIPPET %%

​straightMusic = \relative c' {
  a2 _\markup { no tag, relative pitch } cis4 e |
  fis1 |
}

clarinetOneMusic = \relative c' {
  \set Score.markFormatter = #format-mark-box-numbers
  \tag #'mark { \mark \default a2 _\markup { tag mark, relative pitch } cis4 e | }
  \tag #'no-mark { a2 _\markup { tag no-mark, relative pitch } cis4 e | }
  fis1 |
}

\score {
  <<
    \new Staff {
      \transpose bes c' \straightMusic
    }
    \new Staff {
      \keepWithTag #'mark
      \transpose bes c' \clarinetOneMusic
    }
    \new Staff {
      \keepWithTag #'no-mark
      \transpose bes c' \clarinetOneMusic
    }
  >>
  \layout { }
}

%% SNIPPET %%​

​​

Guy Stalnaker
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