DynamicText + SpanBar collision; #'spanbar-padding ?

[Mark Polesky]

The \ppp collides with the SpanBar in the example below.

\new StaffGroup \relative f' <<
  \new Staff { R1 | f2\ppp r | }
  \new Staff { R1 | f1 | }
>>

Strangely, it seems that none of my three notation manuals
specifically address this (Ross, Stone, Read).  Of course, I
have seen cases in published scores where dynamics do
collide with the span bars, when space is really tight.  But
the png I've attached shows what I think is a more typical
example, moving the notes a little to the right to prevent
the collision.  This image comes from p.6 of the 1924
Breitkopf & Härtel edition of Liszt's piano Sonata in B
minor.

If the consensus here is to retain the current (colliding)
behavior, could someone at least recommend a workaround to
get the dynamics+notes to move to the right as a unit, with
a little padding besides?  Preferably a single setting to
put in a \layout block so as not to have to do this
repetitively in the music expression.

Ideally, we could have something like #'spanbar-padding to
function in the X direction like #'staff-padding functions
in the Y direction.  Or is there already something like
this?  If so, I can't find it.  If not, could this be done?

Thanks.
- Mark

DynamicText-SpanBar.png
Description: PNG image