If you want to suppress the default tab bar then you can override it. For example when working in the context of the My CRM menu you may wish to call a "new" or "find" page. If we used

Response.Write(CRM.GetPage());

then the existing default menu would display. In my example given of calling a page in the "My CRM" context this would be the 'user' tabgroup. This tabgroup is defined under

Administration -> Advanced Customisation -> System Menus

The default menu would create a visual inconsistency of having a "My CRM" type tabgroup being displayed in a page that should not have a tab group.
We can correct this by calling

Response.Write(CRM.GetPage("find"));

This will create the top of the page like the standard "Find" pages. I have previously blogged an example of a find page created in using the COM ASP API, that uses the technique discussed in the article "Action buttons on Custom Entity Find Screens".

If we do not want any tabgroup to be used then we can call a non-existing tab group.

Response.Write(CRM.GetPage("notreallyhere"));