dbml diagram

I inherited a database with many tables and relationships.  As soon as I add all the tables into the dbml, the scene gets terribly complicated.  I find it difficult to look for the exact entity I'm interested in, much less its relationships with other entities.  It would be nice if it is possible to organize the entities into logical groups.  What is a good practice of doing that?  I found the below thread (circa 2007) which started off suggesting to simply create several dbml, one for each logical grouping of entities.  But it finished off with a concern that this is bad.  Are there any new ideas about this?  thanks.


http://social.msdn.microsoft.com/forums/en-US/linqprojectgeneral/thread/4c29f9a8-7e3a-4cbd-a5af-620f8f5aa42b/