Just so you can follow what was posted and what is being argued...
I'm with scribble, in that this is much more videogame like to me than the way 4e handles it, which is "write it down and we'll come up with something if it comes up in the game in a manner in which the results need to be randomly determined." 4e embraces (within a D&D system anyway) freedom both for players, who mechanically define their characters abilities as adventurers but are unrestricted elsewhere and don't have to give up effectiveness as adventurers to color their character; and for DMs in putting the game world back in their hands as opposed to the "hands" of the rules system.
Where does 4e state "write it down and we'll come up with something if it comes up in the game in a manner in which the results need to be randomly determined.". Seriously, I see fans of 4e state this like there is a section in the book that states this when there isn't. It is a houserule not a part of the actual game.
I have seen quite a few proponents for 4e claim that this exact method is how 4e handles skills that are not listed in the gamebooks... I am arguing it is not how 4e officially handles PC's having skills that are not in the book, plain and simple it is a houserule. You seem to be arguing that it gives rules for ad-hoc actions... again, not what I am arguing against. Now that that is clear I will respond to your post...
No not exactly what was said, but that the rules you said that did not exist, actially do exist. You started discussing the merits of the rules, not that the rules exist or not. You asked where people got the idea that it was in the rules in 4E, and I showed you where in the rules that tells DMs how to handle things that the rules do not cover.
No, the rules as stated above in the post I was arguing against is not a rule in 4e... you are showing something totally different than what Thasmodius stated was the way they were handled in 4e. As far as the merits, I started discussing them because they are not the same thing as stated above, and was trying to, perhaps poorly, show you that. I never said 4e doesn't tell one how to handles actions the rules do not cover.
In fact, there is a small section on how to make houserules in the DMG as well. Clearly, that is what is intended, to make the game to your liking, is it not?
Yep, and I stated the rule Thasmodius stated was not in 4e, and that it was a houserule... I don't see how this in anyway goes against what I said.
This has nothing to do with editions or other games. The rules support what you said they did not.
In fact, the page clearly states that if a situation comes up that we do not cover, here is how to handle that.
Sure does and it does not state ...
"write it down and we'll come up with something if it comes up in the game in a manner in which the results need to be randomly determined."
The page shows the DM how to handle a character that has written that he was a Blacksmith prior to adventuring if that where to come up in the coruse of the game. Are you saying that they page does not do that at all?
Now, my question is does it handle it in the same way that Thasmodius states above... if not I rest my case. Does it in fact state if you want a background skill, write it on your sheet and the DM will come up with a system to determine it's effectiveness in gameplay... or does it say hey, here's a way to resolve any ad-hoc action you might want to try that there's no skill for. There's a subtle difference there.
EDIT: The funny thing is that I have rpg's where it is an actual rule that a PC can have a "specialized" skill they made up that gives them the same advantage (bonus to a roll) as a normal skill, but then if D&D 4e had that as an actual rule... a character might end up unbalanced in gameplay.