Why isn’t tiered successes an optional rule in DnD? I can’t come up with a reason why how effective a character is at a SC/ST isn’t changed based on how far away or far above a target number a character gets. Ie if the save is a 15 why don’t i kind of save on a 10? Reasonable optional rule – honestly just hadn’t thought to implement something like that
— Mike Mearls (@mikemearls) November 12, 2017
I seem to recall tiered successes and failures were around in 3.5? Dunno why that’s fuzzy in my memory, but I’m pretty sure.
It adds a bit of complexity and counting, but since it’s on the DM side of things it shouldn’t slow down play much at all. If it does, just drop it. Easy optional rule.
That said, I do feel it starts straying into the territory of things like “Taking 10 / Taking 20”, in that it can potentially trivialize challenges by softening them, and it starts to promote meta gaming through player knowledge.
If success or failure is purely binary, then players don’t really know how much they failed or succeeded by on a check. They can’t plan around challenges by using player knowledge unavailable to their characters.
Example. If the party Rogue tries to leap across a yawning chasm, and they get a 15 and succeed, in a binary system they have no clue how good that is compared to the difficulty of the jump, except that it was “good enough”.
But in a tiered system, the DM is inherently forced to tell them if they succeeded exceptionally or not, which then informs the players that the DC is at least 5 or even 10 points lower than the Rogue rolled.
So now the player of the unathletic Wizard thinks, “Aha! Not that was a two-tier super success! The DC can’t be any higher than an 5! Even with my crappy rolls, I should be able to make that jump no problem!”
But in a binary system, the exact same player and character are a lot more uncertain about the risk. All they know is that an 15 was good enough – they don’t also know that a mere 5 would likewise be good enough.
Consequently, they can’t plan around being able to releably beat the DC. For all they know, the DC could actually be a 10 or a 15, and they’re far less confident about hitting those than they are about hitting a 5. So instead of just making the jump which they know isn’t a big threat, they hesitate and think up other options.