>You may be hepped up on goof-balls, but your memory seems intact --
>people >often recommend that we assign an explicit width to a block
>that's floated in >many circumstances. However, doing so isn't (as
>far as I know) mandated by the >W3C spec and therefore isn't a
>requirement but rather a recommendation by >veteran developers when
>designing certain kinds of layouts involving floats.
You are correct as the current specs stand. However, the original
CSS2 specs did mandate an explicit width. As Adam pointed out earlier
in the thread
There is however no reason that the explicit width one should not be auto
ie, width: auto is perfectly acceptable
Except of course for IE Mac 5 treating that the same as 100%. 
Though there is a solution of sorts for IE Mac 5 - use display: inline-block
That is, if you feel you have to cater for IE Mac 5.
 And possibly some earlier versions of Opera?
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