Good topic. Do I need to take more critical writing classes before commenting?
While I tend to agree that 'broken' is used too much to describe whatever a player/DM doesn't agree with, I do prefer the overall umbrella that 'broken' covers as far as opinions on game mechanics. I would liken it to the definitions 'wrong' or 'bad', and similiarly using 'broken' is a general term, and without degrees of magnitude it looses definition within discussion. Basically, calling something, anything, 'broken' usually has an explanation as to why. Just declaring that it is solves nothing IMO; give it some thought and justify in your house rules, between sessions, anywhere but at the table IMC.
Sometimes I write up some limitations on rules and find myself stating, insomanywords, that certain things are overpowered. Again, this doesn't really solve the problem of why, but it does start to define the subject a little more, and with more iteration and discussion you can follow a path until narrowing all the way through to find out why you think something is 'broken'.
Should we split 'broken' up into separate terms to better communicate exactly what we mean? Don't we already? I haven't seen any posts that matter-of-factly state a rule is 'broken' without some follow up debate. IMO, we just need to say more clearly, well, why.