"Updateless" does describe the weird attitude of that decision theory to observations. It really does not learn from evidence, and it is a problem, so the weird connotations correspond to actual weirdness of the algorithm. In that sense, "telepathic" also somewhat fits, in that the current models of this style of decision making do require the players to have unreasonable amount of knowledge about each other (although merely reading each other's thoughts is not enough), but this seems more like a limitation of current models (i.e. concrete examples of algorithms) than the limitation of the overall decision-making style (it's not yet known to what extent it's so).