How superferry conversions can lead to useful naval transports

Would the US Navy have been better served by building its fast transports from the superferry design as new ships from the beginning?

A common purpose-built class could have been preferable, but the acquired ferries met an urgent requirement and demonstrated a useful design that later construction could build upon.

The answer accepts the attraction of obtaining purpose-built ships of a common class from the outset. The available ferries nevertheless met an urgent requirement when unused ships could be acquired. Their service showed that the underlying design was useful for fast transport. The discussion uses that sequence to explain why an available ship can have practical value even when a theoretical procurement plan promises something better.