The informant is a former Army Ranger who attended West Point Military Academy from 1975-1979. During his time, he was taught many traditions and secrets that were exclusive to the army.
The phrase “Pop it up, take big bites, make sandwiches” was one of such phrases heard at West Point. A “plebe” is a first year student at the academy. If you heard this from a superior officer while you were a plebe, it was a very good thing. It meant that whatever good deed you had done had earned you certain privildges. “Pop it up” was referring to one’s chest. They should stand tall and proud with their chest out for what they had done. The next two phrases have to do with the rules that were enforced on plebes while eating. Like many aspects of being a plebe, these rules were strict and often absurd, but intended to teach discipline. While eating, plebes had to cut up all of their food into small pieces, even things as small as Cheerios. Thus, the instruction to “take big bites” meant that they no longer had to abide by this rule. When sandwhich fixings were available, they were not allowed to make them, instead eating the meat, bread, and cheese individually. Hearing this phrase, however, voided this rule. The informant notes, though, that there were still other required rituals which had to be observed.
The informant remembers this phrase because it was always his goal to hear it. Now, he uses it himself in situations other than eating. Thus, phrase has transcended its original purpose and now is taken as simply a compliment or substitute for saying “good job” no matter the context. Although the rules may have been harsh, the informant cites traditions like this phrase as reasons that West Point helped him succeed.