Show & tell: edge cases vs the alternatives [v2]

Long-time lurker, first-time poster. Spent the last few weekends digging into this and the deeper I go the more questions I have. This came up at a meetup recently and the room was split, so curious what the broader community thinks.

Long-time lurker, first-time poster. Long-time lurker, first-time poster. I want to write something more comprehensive about this later but starting with a quick post to gather thoughts.