The active language will be saved in the DB field. So each time you save you content in a different language all the field are going to be overwrites. I do have the feeling this can be problematic. The first problem I can see is with the change-log:

Proper solution need a database structure change and certainly content translation support in bolt core. Having one table for each language for example. Or best one for each translated field.
As a workaround, always save in the same language in the table field?