Hello,

Earlier I mentioned, as an aside, that OpenGL manuals look bad.  Try 
rendering gluPerspective to see what I mean.  (Attached.)

I tracked this down to the following:

.SH PARAMETERS
.TP \w'\fIaspect\fP\ \ 'u
\f2fovy\fP
Specifies the field of view angle, in degrees, in the \f2y\fP direction.
.TP
\f2aspect\fP

Note that the width of the TP head is being set to the contents of 
\w'xxx'.  So this should be interpreted as

.Tp <width of "aspect  ">u

which should amount to 8 character widths.

However, in roff.c:630, we multiply this width by 24.  As a result, 
everything's wonky.  (8 * 24 = a long line)

At first I thought that we should just yank the 24.  But in running a 
little test, it seems that the \w'' doesn't calculate the string width 
in characters, but in magic internal units.  So it's not that we 
shouldn't multiply by 24, but instead that the "u" scaling unit should 
*divide* by 24.

The test was:

.TH FOO 1
.TP \w'h'u
hello
world
.TP 24u
hello
world
.TP 48u
hello
world

These now display similarly between mandoc and nroff with the enclosed 
patch, though I haven't tested it exhaustively.  Thoughts?

Best,

Kristaps