It is possible to create a Model Inheritance loop

(Bug, Investigate , Priority: High, Test Status: No automated tests yet , Reported By Justin du Coeur, )
Data Model
Summary: Create a Model "Loop 1". Add a child Model "Loop 2". Add a sub-child model "Loop 3". Set "Loop 1"'s parent to Loop 3. Boom! Immediate stack overflows.
The fact that it causes crashes is a separate bug. But it shouldn't be possible to set this up in the first place, especially since it is hard to fix afterwards.