Since you know much more than I do about PostScript and PS printers,
may I ask you a question: if one sends RTL text embedded in a PS
program to a PS printer, does the printer have the capability to
reorder RTL text when it prints it? That is, if you send a string of
RTL characters that way, are they printed in reverse order? Or do PS
printers need the text in the "visual" order, already reordered for
display?

Two things to remember about PS printer:

- It's like dumb terminal which places characters left to right unless specified otherwise.

- It doesn't understand unicode, let alone RTL re-ordering.