(a) Have the option to remove the tab from being placed in the main navigation.
(b) Let's assume that we need to have a tab there, I'd like to suppress the subnavigation that appears below on the second level subnavigation. I know there is a template but removing or hiding the contents doesn't hide the container for the subnavigation, leaving you with a big empty space below.
Suppression means not using CSS to "hide" what is actually there and will appear in the source code and also usually take up space on the page even though hidden and thus, not the appropriate solution. I'd appreciate if someone could help me accelerate my understanding of how this works.