I've been using attribute checks a lot, lately. My PbP game is Beyond the Wall, which uses attributes and additive skill bonuses. At home, I've been playing Holmes with the kid, with straight attribute checks bolted on.
Now, there is a powerful spartan appeal to the default 1d6 skill check of OD&D and B/X. And there's a curvy elegance to the 2d6 check of Traveller and *World. You can use OD&D-style attribute bonuses with 1d6, and B/X-style bonuses with 2d6 without breaking anything. But I've been using using the standard d20 vs. Attribute Score.
Largely, this is because I hate to not use the attribute scores. They are such a prominent part of the character sheet, we expend such hope and energy on rolling them up, and they are so central to how we envision our character—how could we not use them?
With the kid's games, I've found this especially gratifying. The kid grasped the significance of the attributes, and how to apply them to a single roll of a d20. He immediately began suggesting when checks of which attributes were appropriate. And he's taught his friends how to play using this system. Successful transfer from one seven-year-old to another has got to be the golden hallmark of conceptual elegance.
I don't like the math. I don't like the straight line of probability one gets from a d20. A high stat feels too assured of victory, and a medium stat feels too arbitrary. If you're adding skill bonuses to attributes (which strikes me as a pretty straightforward way to handle skills), you have to start imposing limits to make sure characters aren't guaranteed success. And when I add situational bonuses and penalties, I always feel like I'm kinda pulling numbers out of the air.
I've been thinking about this system.
Roll under your attribute on:
2d6 for an Easy task;
3d6 for Average;
4d6 for Hard;
5d6 for Extraordinarily Hard;
6d6 for Total Longshot.
And if you every need a comedy roll to, say, see how long your Charisma 3 Barbarian can last at the Duchess' Tea Party, you can use a 1d6.
Output 1: 1d6 / Output 2: 2d6 / Output 3: 3d6 / Output 4: 4d6 / Output 5: 5d6 / Output 6: 6d6
If you've played with this sort of check before, I'd love to hear your take on it.