Do Americans find a date such as 11 Apr 2012 more readable than the ISO format 2012-04-11? The reason I ask is that there are many situations where we do not have access to the locale, and even if we do there are often no locale-sensitive formatting functions that we can use.
The U.S. military uses the 11 Apr 2012 format (
DD MMM YYYY, or
DD MMM YY), so as to avoid ambiguities between 4 Nov and 11 Apr (4/11 and 11/4, not necessarily respectively, depending on where you reside).
The format is more uncommon outside of military correspondence, but I don't think anyone would tell you that such a date is "less readable" – maybe "less familiar."