Product Meta Tag - Site Tagline Adjustment Failure

I'm trying to adjust product level metatags to remove my site tagline, but I'm running into 2 issues.

a) If I try to make a change on a sitewide basis using the Product Type>Edit Layout menu the changes appear to filter down to the product metatags(changes appear in the radioactive button screen), but the changes don't appear in the browser. For instance I have set it to the following but am still see the site tagline:
Show Metatags Title Default - Product Title 1
Show Metatags Title Default - Product Name 1
Show Metatags Title Default - Product Model 0
Show Metatags Title Default - Product Price 0
Show Metatags Title Default - Product Tagline 0

b) If I manually adjust individual product metatags, the changes don't stick....even for a second.

So my question is.
Should scenario A) control the appearance of the site tagline on product pages? If so, possible solitions? If not, how can I globally implement this change.

Any reasons why scenario b) might be occurring?

Thanks,
lindasdd

If I understand you correctly look at
/includes/modules/meta_tags.php

define('META_TAG_TITLE', HEADING_TITLE . PRIMARY_SECTION . TITLE . TAGLINE);

Kobra,
The only way I could get the TAGLINE to turn off was to literally remove every entry of TAGLINE from the file. Based on the options on the admin side I would think this would be doable without doing that.

-lindasdd