Re: info inconsistency about "Shell Commands in Dired"

[Richard Stallman]

       I saw people discussing other methods, %s and envvars.
       The envvar method is too inconvenient.  %s might be acceptable;
       people mainly discussed how to implement it.

       Let's compare these two methods in terms of desirability as
       features.

    I believe that the method I proposed offers the least deviation from
    the current syntax.  

What method is that?  Is it one of the two I described above,
or something else?