Pedantry alert... this tangent won't be very much fun. Just a heads up for people who only cared about the basic question on the face of the original post...
... And in 6th edition skull explicitly don't count (so we know that we don't have to worry about that either) - but that also mean that the intent seem to be that attribute values for torso now *do* count (at least for activities that involve the whole body; such as sprinting, climbing, swimming, etc).
Actually, the rule is:
"Note that Strength and Agility increases have
no effect when they are included in a cyberskull."
Not that "you don't count the Skull's relevance to an action if, somehow, the head's Strength or Agility is relevant to the action". So if, for example, you're trying to bite someone, the cyberskull's attributes are pegged at the baseline 2 and if you do improve them, the increased value is ignored.
So even if you were to expand that rule to the torso, it wouldn't mean you ignore the torso's relevance in any physical action... you'd be ignoring any values beyond 2. Obviously, this is a hypothetical rule expansion I heartily recommend against.