Theme development

I've noticed just now the use of a class=hide that hides the text on the page. I understand that this is originally a technique to improve search engine ranking, but also that it is now frowned upon. For example, Matt Cutts from Google discusses the practice: http://www.mattcutts.com/blog/seo-mistakes-not-checking-your-site/

Is there any wisdom on this topic? If you agree, I think we should start filing patches to remove this from drupal themes.

Greg

Hi all,
I need to change the layout of the forum pages .. i've customized my page.tpl.php already ...

I was looking at overriding these theme functions:

hi there!
i have a question concerning the theme() function´s granularity. The API sais

If the current theme does not implement the requested function, then the current theme engine is checked. If neither the engine nor theme implement the requested function, then the base theme function is called.

I understand this a a layered approach:

| --- Theme layer
| --- Template engine layer
v --- Drupal layer

How do I add smarty vars without hacking the engine or creating a {set_vars} template function?

I just created my first page module.
But I need to use the completely different page layout for pages generated by the module.
How do I output content from the module via custom theme, not default one?

How would I call a menu manually (e.g. the Navigation menu or a user created menu from admin/menus)?

I could be missing something, but right now it seems these are part of the sidebar_left and sidebar_right variables in Page.tpl.php (http://drupal.org/node/11812). So while I can manually place the search_box, breadcrumb, primary_links, secondary_links and so forth into a new theme I cannot figure out how to manually call a menu since it is part of sidebar_x.

Can this be done? How?