Imagine the scene: Fastfeet the Rogue and Joe Average need to cross a rickety rope bridge before kobolds have time to drop a bolder from the cliffs above. Fastfeet, with dexterity 20, stands as the quickest halfling alive. Joe Average. with dexterity 10, has a hopelessly mundane, non-D&D name. Let’s call him J’oe. Better.

The wobbly bridge has rotting and missing planks, so crossing it without slowing requires a dexterity check. The DM decides that the crossing counts as an EASY check: DC 10. No problem thinks Fastfeet, I’m optimized to have the highest possible dexterity. I just can’t roll a 1…or a 2, or 3, or 4. Hmmm, I may as well try diplomacy.

Fastfeet, the quickest halfling alive, still suffers a 20% chance of missing an EASY check. Despite being the quickest possible character, Fastfeet only gains an extra 25 percentage points in his chance over J’oe average.

The problem stems from the mere +5 that a 20 characteristic adds to the check. The D20 roll swamps it. This leads to two problems:

• Exceptional characters do not noticeably stand out. Whether your character has a poor or a great characteristic, every ability check pretty much feels like a coin flip. This becomes particularly noticeable with checks that encourage everyone at the table to try. That’s when everyone puzzles over an ancient map fragment, the resident sage says she will try a history check, and everyone chimes in, “I’ll try too.” Most times, the expert character gets no chance to shine, because her numerical bonus barely exceeds anyone else’s. The success goes to the person who happened to roll a 19.
• Even when an exceptional character attempts something easy, the outcome remains unpredictable, as in Fastfeet’s case.

I asked Mike Mearls about this issue, and he said that the DM could simply rule that a easy check is an automatic success for characters of advanced ability. The advice patches over bad math with DM fiat. As a DM, I would make that ruling, because the system’s rotten foundation forces it. I would rather see math that works.

You may think that I’m overlooking the skills that address my problem with the math. Forget skills. D&D next has no skill checks or ability checks, only checks. Unlike earlier editions, skills no longer provide a system for determining success, so for example, the skill descriptions no longer include rules for resolution. Skills represent a small number of areas where extraordinary focus and training might help your character make checks.  Skills stand as an optional rule for granting a bonus to a limited number of checks. Most checks rely entirely on ability modifiers.

This means that Fastfeet’s +5 won’t get any better. No athletics or balance skill exists to improve the odds. Even if one did, most characters only get 3 skills.

In 3rd and 4th edition, the DM typically asks for skill checks rather than ability checks. Fastfeet probably has acrobatics skill, granting another +4 or +5 to the check. Suddenly that easy check becomes easy.

Third and fourth edition assumed checks would be skill checks, so both the skill and ability contributed bonuses. Next assumes ability checks. Skills add an unusual bonus rather than an inevitable addition.

I think this simplification makes for a better game. In addition to the virtue of simplicity, an over-reliance on skills tends to encourage players to solve problems by looking at their skill list, rather than thinking about other things their character could do in the game world.

I like the new approach, but in D&D next, the system’s numbers still seem to assume characters always get a skill bonus stacked with an ability bonus. In practice, a first level character gets a maximum bonus of +5 to a typical check. Little mathematical difference exists between a character with extraordinary ability and one with average ability. In third and fourth edition, a level 1 character like Fastfeet saw a bonus closer to +9 or +10, big enough to make a practical difference.

The solution seems obvious. For checks, the ability modifier must double, to +1 for each ability score point over 10. Now Fastfeet enjoys a +10 to dex checks, appropriate for the quickest halfling alive and consistent with the bonus typical in earlier editions.
Obviously, Fastfeet cannot also enjoy a +10 on his bow attacks. The original modifier scale must remain as combat modifiers, separate from ability check modifiers.  The two scales introduce a small, necessary complexity.

On the other hand, calculating ability modifiers becomes easier. A character with 15 dexterity has a +5 ability modifier. As an added bonus, odd-numbered ability scores gain significance in the game. Suddenly 15 really is better than 14.

I realize this change bucks the history of ability modifiers established in 3rd edition, but I can trump that with an earlier precedent.  Check page B60 of the Moldvay basic set from 1981. “To perform a difficult task, the player should roll the ability score or less on 1d20.” The mechanic flips the numbers, asking for a low roll, but your ability score has the same numerical effect as the modifiers I suggest. In the late 70s, I saw this mechanic used frequently. So the change qualifies as old school and it fixes the system. Seems like a win.

Still not convinced? Consider this. Over the course of an adventure, an exceptionally-strong fighter might make a hundred attack rolls. The +5 attack modifier she gains from her 18(00), I mean 20, strength improves them all. She dominates the battlefield. Over the course of the same adventure, the smooth talker with a 20 charisma may get 8 diplomacy checks, tops. Over the course of so few rolls, the 1-20 spread of the die buries the mere +5. The diplomacy skill can help. Still the most charming person you ever meet, in game terms, seems little better than the half orc who picks his nose as he negotiates with the elf king. The player who optimized the smooth talker hardly gets a chance to shine.