[texhax] The Em Rule, a Question of Style

[Philip TAYLOR]

P. R. Stanley wrote:

> Thanks for your response. So, would you say that mbox and the ~ are
> interchangeable in this instance?

Without looking at the definition of \mbox one cannot be
certain, but I would hypothesise that \mbox creates a
single indivisible unit that cannot possibly be split
unless it is \un[*]box'd, whilst the tie ("~") simply
inhibits splitting at one particular place, allowing
other potential breakpoints to still have their
intended effect.

Philip Taylor