jordanjay29 I think OP wants to see all discussions only tagged with the top level tag, and filter out the subtags until they are clicked.
I understand that, but in which way are these tags sub-tags then?
@robinodds
I understand now what you want to achieve, but as @jordanjay29 mentioned already this is not possible with the stock software and there is so far no extension that provides that. It should be doable quite easily though for someone with the necessary skills.
But beside that, I don't understand your intended usage.
Let's say your tag is automobiles and you have sub-tags for different brands. If you'd exclude brand-specific discussions from the main tag, you'd have to describe it as non-brand-related discussions about automobiles, but then the brand-specific tags wouldn't fit as sub-tags anymore.
Could you give an example what kind of tags you think about?