Layout behaviour arising from '\set chordChanges = ##t'

[Jim Long]

Kieren's request for a ! shortcut in chordMode brought a slightly
related issue to my forebrain which I have been dealing with
quietly in the past.

Based on the example below, it appears that the net result of

\set chordChanges = ##t

is that repeated chordnames are made invisible, but space is
still reserved for the chordname markup.

If that is correct, is there a technical preference for making
them invisible, rather than simply not stenciling them at all and
therefore using no space to represent invisible repeated chords?

This usually manifests as increased note spacing resulting from
invisible chord names in an aligned chordnames staff, most
noticeably when the chordname markup is sufficiently lengthy
(such as when many altered chord degrees are spec'ed).

I have a workaround for this (use spacers) but I'm curious whether
this behaviour is intentional, and preferable to the option of 
having repeated chords not be stenciled when chordChanges = ##t.
And I suspect my workaround would not be satisfactory for users
who rely on MIDI output.

The example could be better, but it shows the behaviour I describe.

Thank you!

Jim


%{
Example to show how invisible chordnames still take up space.
%}

\version "2.16.0"

\score {
  <<
    \new ChordNames \chordmode {
% 'narrow' chord markup fits fine:
      \repeat unfold 2 { aes8 q q q q q q q }
% 'wide' chord markup takes up space:
      \repeat unfold 2 { aes8:7.5-9- q q q q q q q }

      \set chordChanges = ##t
% 'wide' invisible chords still take up space:
      \repeat unfold 2 { aes8:7.5-9- q q q q q q q }
% workaround is to use spacers
      \repeat unfold 2 { aes8:7.5-9- s2.. }
    }
    \new Staff \relative c' {
      \repeat unfold 4 {
        \repeat unfold 2 { c8 c8 c8 c8 c8 c8 c8 c8 } \break
      }
    }
  >>
  \layout {}
} % score