image replacement question
so, I've played with image replacement before, but now I'm going to use my brain:
The designer specifies, through CSS, that the image will display in most cases; if it should not display for some reason, the underlying structural HTML markup is supposed to take its place.
The advantages here are a nice graphical appearance most of the time and markup somewhat more elegant than
<h1><img alt=""></h1>, which is pretty much your only alternative if, say, you want to use a picture of text as a headline. Because it does not nest an image inside a heading, FIR is at least superficially better for accessibility.
HTML already has a mechanism for accessible image replacement, and everybody knows about it! Isn't this the stated purpose of
alt text? How is adding an extra, empty
<span> "more elegant"? Is alt text not indexed by search engines? (wait, it is) Will screen readers deal more predictably with a series of hacked-up CSS image replacement techniques than with something that is part of the HTML spec? Is it better to fail unpredictably than to have a consistent behavior across browsers? Also, why aren't screen-reader makers a prominent part of the web-standards discussion? (Or are they?)</rant>
Serious responses considered.