Why a carrier should not have two angled decks

What would it take for an aircraft carrier to have two angled flight decks?

It would introduce hazardous emergency flight paths and major expense, with little advantage over building two carriers.

An aviator in an emergency needs an instinctive and unambiguous escape direction. A second angle could point an aircraft toward the island or force a pilot to choose between conflicting paths under extreme time pressure. The extra deck area, structure, and machinery would make the ship larger and more complex. There is little advantage when the cost could approach that of two carriers, which would also provide operational flexibility and redundancy.