commit 24d4975ebe515a9e3530c738822603aeccb96cde
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
Date:   Fri Jul 12 10:01:40 2024 -0500

    [nroff]: Support argument clustering.

    * src/roff/nroff/nroff.sh: Support argument clustering by iterating over
      the argument list and declustering options that can be clustered
      (`-abCEikpRStUzZ`).

    * src/roff/nroff/tests/verbose_option_works.sh: Test it.

    * NEWS: Document it.

    Fixes <https://savannah.gnu.org/bugs/?64684>.

This is unfortunate.

$ groff -atz ./EXPERIMENTS/simple-table.roff # successful
$ nroff -atz ./EXPERIMENTS/simple-table.roff
/home/branden/groff-stable/bin/nroff: usage error: invalid option '-at'
usage: /home/branden/groff-stable/bin/nroff [-bcCEhikpRStUVz] [-d ctext] [-d string=text] [-K fallback-encoding] [-m macro-package] [-M macro-directory] [-n page-number] [-o page-list] [-P postprocessor-argument] [-r cnumeric-expression] [-r register=numeric-expression] [-T output-device] [-w warning-category] [-W warning-category] [file ...]
usage: /home/branden/groff-stable/bin/nroff {-v | --version}
usage: /home/branden/groff-stable/bin/nroff --help

Might be tricky to handle in a shell script.  Could require recursive parsing, or "unshifting" arguments onto the list in addition to the well-trodden ground of shifting them off.