Originally Posted by puddin' legs
At the risk of being rude, can we assume that the mountains you're riding aren't in Minnesota? So that would mean that you're travelling to ride in territory and conditions that you ordinarily don't? That would explain the 30t rear cog, but my guess is (and it's only a guess) that if you lived near those moutains, you probably wouldn't find much use for those 30t unless you're touring loaded.
Minnesota has no mountains. I use a 12-23 or 12-26 around home which gets me up 18% grades (they are short). Even when I go to the Rockies or Smokies or Alps, I don't use the 30t a lot - only for long stuff over 10%. But I wouldn't want to be without it.