The phrase, to be at 6's and 7's implies that you are at a loss, or in a state of ineptitude where you cannot reliably take acton.
The saying originates from a situation in 1327 and relates to the Guilds of Tradesmen in the City of London. The Merchant Taylors and the Skinners were founded within a few days of each other, five other Guilds having already received their charters. The age of each Guild dictated its position in the Lord Mayor's procession. The Merchant Taylors and the Skinners argued for fifty years as to which should go sixth in the procession. In the end, Sir Robert Billesden, the current Lord Mayor, decreed that they should take it in turns to go sixth and seventh.
Their defense was in utter shambles. They couldn't do anything right. They were at 6's and 7's.
2 and 7 guy: "I love Mumford and Sons! They are the greatest band ever!"
Real Mumford and Sons Fan: "I know! After the Storm is a work of genius! What's your favorite song?"
2 and 7 guy: "Well, I only know The Cave and Little Lion Man..."
Real Mumford and Sons Fan: "You're such a 2 and 7!"
A score made famous by Jon Hendriks, in a Counter-Strike: Source scrimmage. He did not get any kills, but managed to kill a teammate in the process. After further embarassment, Jon is still ridiculed by this lousy score to this day.