What I Would Do With […] Groceries [dy/dan] Nat Torkington on O’Reilly Radar explains it thus: read this and you will realize that Dan Meyer is the math teacher you wish you’d had. He has the geek nature, and his excitement must be great for his students. The express lane isn’t faster. The manager backed me up on this one. You attract more people holding fewer total items, but as the data shows above, when you add one person to the line, you’re adding 48 extra seconds to the line length (that’s “tender time” added to “other time”) without even considering the items in her cart. Meanwhile, an extra item only costs you an extra 2.8 seconds. Therefore, you’d rather add 17 more items to the line than one extra person! I can’t believe I’m dropping exclamation points in an essay on grocery shopping but that’s how this stuff makes me feel.
What I Would Do With […] Groceries [dy/dan]

Nat Torkington on O’Reilly Radar

explains it thus:
read this and you will realize that Dan Meyer is the math teacher you wish you’d had. He has the geek nature, and his excitement must be great for his students. The express lane isn’t faster. The manager backed me up on this one. You attract more people holding fewer total items, but as the data shows above, when you add one person to the line, you’re adding 48 extra seconds to the line length (that’s “tender time” added to “other time”) without even considering the items in her cart. Meanwhile, an extra item only costs you an extra 2.8 seconds. Therefore, you’d rather add 17 more items to the line than one extra person! I can’t believe I’m dropping exclamation points in an essay on grocery shopping but that’s how this stuff makes me feel.

Notes