The -w and -W options behave differently and produce different output when
the stdout is a tty tty than when it is not, e.i.
$ man -W info
$ man -W info | cat
$ man -W info | more
I haven't checked the source code, but I imagine that there is a test
for 'isatty' early in the man program to determine whether or not to
utilize the preformatted 'catman' pages. This test should always be true
when the -W or -w options are in effect, otherwise it is easy to miss the
source of corrupted man pages.
Incidentally, the 'man' manpage mentions the ability redirect the output
of -W but does not say anything about the fact that the output will be
*different* than if you just let it go to a terminal. I don't think the
man page is incorrect for this oversight; I think the behavior is broken.
Fixed in 1.5i-1