A quick inquiry...

[Jhaelen]

I think there was chat on this board about changing resistences from armour to a threshold (i.e. if you go over ALL damage is applied)[...]HOWEVER this was just chat on the board and never linked to something WotC intended to do. (although I vaguely remember mention of DDM games)

Well, the 4E rpg stats of the Grick has the following:

Resist damage threshold 15

So it looks like it might be in the game in addition or as an alternative to the standard resistances.