Sorry to continue here, but I think there's is still a problem.

I agree that I'm not taking advantage of Hibernate's optimizations doing that way.

But, when I'm doing clear on the map/collection property of the entity, it clears too the argument map/collection (I have others simple examples showing this problem). I test the two objects (the property and the argument) and they are not the same. So, the clear operation is propagate to the argument somehow and that is an issue.