[thelist] re alt tags google vs accessability

[Boldacious]

Hi

Google now uses alt tags in their description of sites.
And we are supposed to use the alt tags for accessibility (mainly
for sight-disabled or "images-turned-off" users)
So if I have a header logo on every page which links to the home
page I should have an alt tag which says "my site logo - link back
to home page" or something like that. However that is useless for
google which will include this text in the site description.
How do we get around this - it seems to me that we have a choice -
search rankings that make sense in google OR alt tags that make
sense for sight-disabled or "images-turned-off" users. And these
two aims seem mutually exclusive.
Any ideas?