Check out Marrero's defensive stats, he really isn't a good example to illustrate your position.

He's always been primarily a catcher, and has spent the majority of his defensive time behind the plate, except this last year where he played 2 more games in RF than at catcher (because of Drew's injury problems).

44 games and 180 innings makes his qualified as a catcher in my book, and an owner should be able to use every one of his 446 PA's as a starting catcher.

Jon