Maybe because they could master just one disc for both europe and japan, and let the player decide which sountracks are available... indeed, I think few people in europe set their BD player's main language to japanese, and vice versa...

Ah, they are really smart... any opportunity to spare some cash is welcome... after all, they recycled the whole trilogy from the HD-DVD, so...

About dropping sountracks: as I discovered some imperfections, I should re-render (again? yes...) the whole movie, so I will drop all the secondary commentary tracks only if I could find the german soundtrack.

About bitrate: I calculated it so well, that it's really close to the original one, so it's useless to increase bitrate over the original one, don't you think? And final result is really, really good! In comparison to the BD, in nearly perfect; in comparison to the regraded version (that is very good, by the way) it's better.