Which timesteps are created?

[Lukas-Fabian Moser]

Folks,

I'm not quite sure how to phrase my question resp. whether it's 
meaningful at all, but here goes: Which mechanisms control the creation 
of time steps?

Consider:

\version "2.23.10"

\new Staff
<<
  \new Voice \with {
    \consists #
    (lambda (ctx)
      (make-engraver
       ((start-translation-timestep engraver)
        (ly:message "Seen timestep: ~a\n" (ly:context-current-moment 
ctx)))))
  } { s1*5 }
  \new Voice { s4 }
>>

Output:

> Seen timestep: #<Mom 1/4>
> Seen timestep: #<Mom 1>
> Seen timestep: #<Mom 2>
> Seen timestep: #<Mom 3>
> Seen timestep: #<Mom 4>
> Seen timestep: #<Mom 5>
This shows:

a) We see a timestep at the end of events even in _other_ contexts than 
the one the engraver lives in.
b) We see a timestep at every bar boundary.

I'm interested in b): Can I increase the density and, e.g., force a 
timestep to be created at each 1/4 moment? (Apart from the obvious 
possibilty of adding a Voice consisting of \repeat unfold ... { s4 }.)

Lukas