The spec suggests that <kbd> and <samp> elements can be nested in
different ways to represent different things.
http://www.whatwg.org/specs/web-apps/current-work/multipage/section-phrase.html#the-kbd
This was discussed on IRC:
http://krijnhoetmer.nl/irc-logs/whatwg/20070615#l-294
Summary:
* UAs can't do anything useful with the information.
* The reader can understand the intent by the context.
* A single level of either <kbd> or <samp> is enough for common styling
needs. Even if it isn't, a class on the outermost element is more
helpful due to lack of parent selectors in CSS.
* It's extremely verbose. Compare:
<kbd>File</kbd> > <kbd>Exit</kbd>
...with:
<kbd><kbd><samp>File</samp></kbd> > <kbd><samp>Exit</samp></kbd></kbd>
* Fiddly markup inevitably causes confusion and is easier to get wrong.
* People can nest the elements if they like (e.g. for more complex
styling) without this being required. An example might be a page that
contains both text to be entered and keys to be pressed, with those
being styled differently.
* <kbd> is already used in the wild to represent keys to be pressed.
--
Simon Pieters
