My dad is friends with some Shimano reps and they confirmed what you said that the Catala is made in Malaysia using cheaper labor and a less-expensive die-cast frame, and the Calcutta is made in Japan. Don't know that it makes much difference, since the specs are all engineered in Japan anyway. But the cheaper labor is what helps them price the Catala at a lower price point.

** tight lines make all my troubles go away **