Do Pre-gens need a strong GM Hand?

This is the first of two posts about pre generated characters or pre-gens. I have been thinking about them a lot recently and thought I would get some ideas down.

In a recent game it started out as being intended at a one off session and set at about 10th level. The GM then took four characters from Heroes and Rogues and modified them slightly to fit his idea for the party. He stripped out skills, changed weapons and armour skills and other modifications. He like me feels there are too many skills in RM2 but that is a different can of worms.