Scribble said:This is a bit tricky though. If he sticks to why in the context of a "core" game certain rules are overpowered, I think it will be ok. It's important to remember though, that one group's out of balance might be just right for another and that the various companies exist to fullfill these varying wants and needs.
This is the point I was going to make. Certain people run "low magic" worlds, for example. In this instances, it's entirely possible that the core wizard and sorcerer are "imbalanced".
It's also conceivable that someone may run a world where 75% or greater of the adversaries faced by his players are undead. In that case, having a option for higher-level rogues to sneak attack undead (maybe at reduced effectiveness or maybe only with blunt weapons against zombies and skeletons or something, for example) could still be "balanced."
I think it's important for DMs (and players) to consider the context of their game before evaluating something to see if it's balanced.
Some things are just straight out over-the-top, but other things which may appear at first glance to be completely imbalanced may be just right for someone else's game. By being well-read in the category, you start to get a feel for the type of stuff that each publisher puts out and can start to make judgment calls as to whether something may be appropriate for your campaign.