2009/1/6 Grabovský Matěj <65s.mg(a)atlas.cz>cz>:
The \, command enforces that the formula will be
*always* rendered with TeX.
Actually, it doesn't, \, is just a space which can be rendered in
HTML, just not simply. If you have your preferences set to always use
HTML where possible, even if it's a mess, you'll get \phi\, in HTML,
by default you only get HTML where it's simple. To force PNG in all
cases, you need something like /,/! (a space followed by a negative
space) which can't be done in HTML.