Hi,
The short answer is "no". Composer does not have a "tab" or "indent" feature for Systems.
That said, you could (if you're not going to number the measures)
- leave a blank measure at the beginning of each system where he wants an indent (use Layout/Page layout/Move barlines and staves to adjust the "indent measure"),
- save the score as an image file,
- then take it into a graphic editor (even Paint would work) and
- white out (or erase) the "indent measure" before printing.
If you do that while having measure numbers visible it will goof up the numbering for the printout. Rather, you could include Rehearsal marks in the song file to side step that problem.
Hope this helps.
ttfn,
Sherry