How Does DBCC CHECKIDENT Really Work When Resetting the Identity Seed (RESEED)?

Does resetting an Identity Seed to a specific value via DBCC CHECKIDENT(..., RESEED, new_seed_value) work the way the documentation states? It depends 🙃

Beware! Beware of Unintended Changes When Altering Columns!

Beware of big green dragons, er, well, of unexpected changes when changing a column's datatype. You might be unpleasantly surprised! 🙀 Beware!