I don't think that ease of breaking is in question here. M&M is an incredibly versatile system that allows players to create any character they can think of without cramming them into artificial constructs such as classes. However, as we all know, flexibility and abusability are directly proportional to one another. Just look at some of the monstrosities that get submitted to any mid level D&D 3.5 game when there is a wide open field of sources available.
The point here is to take three specific powers and give examples of the most common exploits that new GMs may miss so that they can be prepared in case a player (intentionally or otherwise) submits a character that takes advantage of them.