> What i'm concerned about is traditional roff. If you extend man, a
> few people will start using these extensions in their new manuals,
> so you gratuitiously make life harder for people trying to still
> support platforms using traditional roff variants that don't have
> these extensions.
This concern is not justified IMHO. From an-ext.tmac:
.\" The code below provides extension macros for the `man' macro package.
.\" Care has been taken to make the code portable; groff extensions are
.\" properly hidden so that all troff implementations can use it without
.\" changes.
.\"
.\" With groff, this file is sourced by the `man' macro package itself.
.\" Man page authors who are concerned about portability might add the
.\" used macros directly to the prologue of the man page(s).
I think this says all.
Werner