Quote Originally Posted by EggKookoo View Post
The rules also don't tell you what CR to make encounters. Sure, it tells you that roughly CR = average party level is a moderate-difficulty encounter (and Xanathar's refines this formula a bit to handle increasing PC power at higher levels), but it doesn't tell you how often the DM should be hitting the party with moderate encounters. Or if they should always be moderate encounters. DMs are left to build their own encounter patterns.

So you come to my table and I like to hit the party with harder encounters. APL + a little bit. I'm not a killer DM. I just think it's more fun if you have to work harder. I give you good rewards. Is this a sign that the game is broken? Or am I just tailoring my game? Is it MMI because on average the monsters you fight have 1 more AC than the ones you fought in someone else's campaign? Not because I'm tweaking the monsters, but because I'm hitting you with higher CR encounters a bit more often.
That switches the problem from the game to the DM. If you constantly set the party up against encounters too hard for them I may very well call you a Killer DM even if you think you're not. If I don't like your game I'd leave, but I know the issue is me not preferring your taste, not the game's rules.