I've been looking for a way to strip down user profile pages to give them a different (but not "new theme" different) look. I think I've found what I want, by addng this php code to my page.tpl.php, before the BODY tag and after the tag.

$isprofile = FALSE;
if (arg(0) == 'user' && is_numeric(arg(1)) && arg(2) == '')
{
   $sidebar_left = '';
   $isprofile = TRUE;
}

Then I used $isprofile to conditionally wrap yet another div around my entire content, including breadcrumb, content-title . . . everything.

This extra div allowed me to override other CSS styles used for the rest of the site, including the style for the content-title and tabs, which can't be styled conditionally based on where in the site you are by default. I also got rid of the breadcrumb on profile pages by adding a drupal_set_breadcrumb(array()); to my user_profile.tpl.php

Is there a cleaner or "best practice" way to do this instead?