This, plus with some older boxes you don't even need to do any of that to cherry pick the cards you are looking for if you know the printing runs. Because companies would just cut cards from the sheets and fill them in the packs without shuffling/randomizing them, all you need to do is open one pack, check the numbers of the cards and where that pack was in the box, and you would know which packs have what. Like knowing the patterns in Pac Man.
I worked in a card shop during high school and college, then owned one, and still remember all of the valuable runs (to find Griffey Jr. Upper Decks, Frank Thomas Leafs, etc.), what tricks were used to search for inserts, "finger-fleecing", etc. You either had to know them so you could spot the customers that were trying it or you learned them the hard way when a wholesaler or card show dealer scammed you. Sometimes you just naturally figured them out from breaking down so many boxes to sell the good cards, make sets, or have commons. I loved learning those things, how to spot counterfeit or trimmed cards, etc. in order to make sure my store, and the things we sold, could be trusted.
I've since left the business but realized recently how "using my powers for good" carried over into my career in financial services Fraud Prevention where I have to think like, and know how to be, a bad guy in order to stop them.