Lessons learned:

Get a juicer. One of those disks with a tiny Sydney opera house on top would be sufficient. At any rate, don't juice limes by hand when the hand in question had paper cuts.

Crushing graham crackers is cathartic.

Sweetened condensed milk does not "pour". It...what's the term for how glaciers move?

Conclusion: Key lime pie is way easier than I was led to suppose. And when the recipe says let it chill before slicing, it means it.