From what I read last night a out it, the phrase comes from the rarity of the blue moon itself. As the last one of them was in 2012? and the next isn't until 2018 or something. Other than that... No idea. Lol
I am hope'n to be there. If the person that's supposed to go with me bails tho (as it seems they might) I WILL be there. if not, I have to wit for them to get off work first. :( Either way, I'll be there this weekend until After Monday's Practice!