Is the TTLB rating system worthless?

OK, I've not been blogging for the past two weeks, because I've had lots of other stuff to do. That happens sometimes, I'm no Michell Malkin or Instapundit.

I have a link to the TTLB at the bottom of my sidebar. I've watched my ranking with them fall from "Large Mammal" all the way down to "Insignificant Microbe".

To me, "Insignificant Microbe" should be for a blog that nobody reads. Yet, during the past two weeks while I have not been blogging, my blog has still been getting lots of visitors, many more hits per day then when I first started blogging. Yet I'm supposed to be just an "Insignificant Microbe" in the TTLB ecosystem, the lowest rating they have?

That doesn't make sense to me. I'm beginning to wonder if the TTLB rating system is actually meaningless, and if I should just delete it from my blog and be done with it. I really can't think of a reason why I SHOULDN'T delete it. Can you?

UPDATE 01-09-08:

It's gone back up to "Large Mammal". But if it keeps jumping around like that, I may just delete it.