I will just repeat myself because I think my idea is very good:
For PICKING conditions, the ELSE should reverse the picking, i.e. the ELSE should pick all instances that were not picked by the IF, REGARDLESS of what happens in the actions (i.e. if in the actions you alter some variable that would cause an instance to match the inverted condition, the ELSE should still not pick it, because the original IF picked it already).
The picking ELSE should think in these terms: was this instance picked the first time? Yes - drop it. No - pick it.
For picking, it should be "instance-wise else".
I have spoken. <img src="smileys/smiley17.gif" border="0" align="middle" />