from the xp dept.
The coach pointed out the relation with Rigidity and all of sudden something familiar came to my mind.
In the last years I've worked on a well-covered projects where almost every new feature required a tremendous effort fixing the entire test suite. The real problem there is in objects with very low cohesion and high coupling that prevent us to concentrate on a specific area of the code when thinking about a concept.
In that team however all the people were smart and "fast", so the underlying problem was, in fact, dominated with Bruce Force. The problem with Brute Force is that it doesn't scale well, and prevents you to really go at full speed.
So, don't use Brute Force in your projects ;-)