Well, really, all that page 42 is some guidelines (errata'd very early on) about how to adjudicate "actions that the rules don't cover". That's the title of the section.
I'll quote some bits:
Your presence as the Dungeon Master is what makes D&D such a great game. You make it possible for the players to try anything they can imagine. That means it's your job to resolve unusual actions when the players try them.
That's the basic idea behind "stunting", though many in the community think that you can't/shouldn't be able to try anything you can imagine.
It talks about using a +/- 2 or granting Combat Advantage to cover many situations.
It talks about casting the action as a check; that is, you make an attack roll against a defense or a skill check against a set DC based on ... something. (There's a table of DCs that was errata'd pretty heavily, and it's unclear if you select the DC based on the
PC's level or the
opposition's level. I think the text leans pretty heavily towards the PC's level, but I think that's lame so I use the monster/trap/hazard/threat's level.)
Based on success,
something happens. It doesn't talk about Conditions like Stunned, Blinded, Dazed, Weakened, etc.; it does have a very handy chart for damage separated into 6 categories (low-med-high for "normal" and "limited"). It says to use the limited damage expressions (higher values) for things that can only happen once, and the normal damage expressions for things that can happen all the time. edit: Damage is also based on PC level.
No mention of niche protection or grounding something in what's happening in the game world at the time, but it does have an example that "makes sense": someone wants to swing from a chandelier and kick an ogre into a flaming brazier, so they make an Acrobatics check to grab the chandelier and swing, then an attack roll to push the ogre 1 square and into the fire.