> Of course the keyword w(...) in the table format line, [snip] > specifies a *minimum* column width. So it will not do > for setting a maximum column width, especially where there > are long text blocks in some cells. > > The following example shows how to do it in general. The > basis is that a ".ll" request in a text block sets a line > length and this will be reflected in the resulting column > width (unless something else, e.g. a long entry which is > not a text block, forces a wider column). [snip]
In this particular example, the table will be formatted *exactly* the same if you leave out the ".ll" requests in the text blocks and instead use the following table specification: | l | lw(3i) | lw(1.25i) |. This is because tbl does exactly what you're doing manually, namely setting the line width to whatever was specified as column width before processing the text block. (Take a look at the output of tbl before it is fed to troff.) As you correctly note, it's called "minimum" column width because tbl cannot guarantee that you have non-text-block items in the column which are wider than what is given in the spec (or text blocks which cannot be broken to this width). The trouble with using the ms paragraph macros in the text blocks is that they themselves reset the line width, overwriting whatever tbl has set up for that text block.
