The Rules

First, all extant rules about advancing skills are abolished. Instead, skill training comes in several distinct pieces

General Heroic Knowledge

You gain a flat bonus to all skills equal to half your level.

Background Training

At first level, you gain a number of ranks equal to your normal amount of skills per level. You may place these ranks in any skill, and place any number of ranks in a single skill. The effect of ranks is described below.

Specific and Ongoing Expertise

At 1st level, and every 3 levels thereafter, gain an additional rank (this is in addition to the Background Training ranks). You may place this rank in any of your class skills, and there is no limit to how many ranks a single skill may hold. If your class would normally gain 4sp or more per level, you also gain a rank at 2nd level and every three levels thereafter. If your class would normally gain 6sp or more per level, you also gain a rank at 3rd level and every three levels thereafter. If your class would normally gain 8sp or more per level, you gain two ranks at 1st level and every level thereafter. This pattern continues for variant classes with even higher skillpoint gains.

The Effects of Ranks

Each rank you have in a skill allows you to roll an additional d20 whenever you use that skill. You take the highest roll among all the dice as your result. For example, if you have 3 ranks in Tumble, you roll 4d20 and take the highest roll. If a skill is Trained Only, having a rank in it makes you count as Trained.

Feat Changes

Skill Focus now gives a +5 bonus. Skill Affinity gives a +3 bonus to two skills.

The Reasoning

D&D's skill system is clunky. Assigning skills takes an enormous amount of time for anything other than the trivial "Max N skills and call it done" approach, and is extremely prone to error. Most classes have so few skill points that they'll only actually train a handful of skills, and only from within their class skill list. By mid levels (if not earlier) the difference in bonuses between someone who trained a skill and someone who didn't are so profound that something is either trivial for half the party or impossible for the other. Setting up obstacles meant to keep out the average person will often keep out half of the party as well unless you design them very carefully. Many fun, innovative situations are stricken from the game because they are best run through skill checks and half the party doesn't have the appropriate skills.

This isn't Heroic Realism. In Heroic Realism, heroes get better at everything. Simply by virtue of being higher level, all heroes can scale a wall, swim a river, chase down a villain on a horse, bluff their way past guards, unlock the barred door, or play an instrument passably. It's just how novels work, and the stories are better for it. Games are better for it, too, when you can depend on the entire party to have at least a minimum of ability in whatever skill you might challenge them with. Rather than having to sit out an adventure segment, everybody gets to participate all the time. Sure, some people are better than others, but it's never so much that the less-skilled party members are useless, unless there's an obvious and significant difference in power (and thus level).

This is all fixed by General Heroic Knowledge. However, this makes characters pretty generic. In order to allow for some appropriate but not overpowering differences between characters right from the start, Background Training is introduced. It is purposely not tied to class skills to allow a wide range of character flavors.

Practiced Skills are where it gets interesting. Bonuses to a skill don't represent experience, they represent knowledge. Anytime I increase my bonus, I'm making some previously possible things certain, and some previously impossible things possible. Within my range of possibility, though, everything is equal. I'm not consistent. Experience, though, I define as the interconnection of your existing knowledge, the set of tips, tricks, and heuristics that help you use the knowledge you have. A low-level problem can still stump an experienced person, but it's very unlikely. Similarly, they still fail rather often at difficult tasks, but much less than they would otherwise. The knowledgeable person only becomes *good* at something when they've mastered the theory behind it and can perform the task without thinking. The experienced person may still fail at the task from time to time, but can call themselves 'good' at a much lower skill level.

Multi-dice mechanics are the natural, most elegant way to represent this. While everyone in the party will have roughly the same skill bonus, those who are trained in it are much more likely to roll high. In tense situations, they're still the ones you turn to. Plus, this mechanic scales essentially infinitely, because every additional die adds less of a bonus. If a player really felt like giving all of their additional dice to a single skill, they could do it without breaking anything. A full 27 ranks in a skill gives you a 75% chance of rolling a 20, but that only amounts to about a +9 bonus on average. Putting a single rank in three different skills gives you more than that, as the first dot is equal to a +3.5 bonus on average.

Many thanks to Yobgod, who gave me a bunch of sass but basically wrote the final draft you see here.