The ADO.NET Entity Framework relies heavily on visual modeling tools. But are these tools really appropriate for large scale development?
In a piece titled Visual Designers Don’t Scale, Scott Allen talks about the problems of Visual Scalability. Essentially this problem comes down to the sheer size of the diagrams. When you have to deal with hundreds or thousands of tables,
They are difficult to navigate, and impossible to search. The layout algorithms don't function well on these large datasets, and number of mouse clicks required to make simple changes is astronomical. The best you can do is jump into the gnarly XML that hides behind the visual representation.
He goes on to predict a change back to textual representations of data models.
Ayende Rahien also sees problems with source control. In reviewing the source control support for the visual designer he discovered that even minor changes in the position of a single screen element could cause merge conflicts. Now imagine the mess if someone were to mistakenly hit the auto-layout button and all the table/entities were moved.