You are well into the edit and need to shorten clip B/2X in the above sequence. Unfortunately, the duration of the scene is already locked. What are your options? Well, you could use a dual roller trim at the edit point between B/2-X and B/1-A, but that would change the head frame edit on B/1-A, which is undesirable. Alternatively you could slide B/1-A, but that would change the head frame edit on BA/3-X, which is also undesirable.
In Media Composer version 3.0 we’ve provided a new trimming technique that not only solves this problem, but many other similar problems