Quote Originally Posted by Just to Browse View Post
Where is that specified? Neither my copy of the 4e PHB or the 4e Rules Compendium have any guidance about that.
It took me a while to find it again, but I think the bit I was thinking about is in DMG2, p. 82: "Is there a chance that a really good idea could completely trump your skill challenge? Don't fret! That's a good thing."
There's more relevant context around, and to be fair it doesn't specifically call out ending it early, but...

In general I'd recommend anyone interested in the ongoing discussion here to read the DMG2 on skill challenges. The initiative thing is gone already by then, of course, because it's stupid and no one likes it, but besides the touch-ups to the rules it also has a ton more discussion and advice than DMG1 offers, and I would argue it makes it clear that the straitjacket interpretation of the rules is not intended, but that it's a structure for the DM to embellish as they see fit.
Power and ritual use is also furthered strengthened on p. 86. DMG1 mentions utility power and rituals enabling alternative skill uses and granting bonuses, but also rituals in particular granting an automatic successes or removing failures (DMG1 p. 74). DMG2 goes so far as saying relevant ritual or daily power usage deserves at least 1 automatic success. It also introduces the rule of thumb to treat non-skill use (powers, resource expenditures, for instance) as secondary skills in terms of benefits gained from them.