This is interesting - apparently, you can execute a "super super" (starting as far up the chain as you like) in VisualWorks. Eliot Miranda posted this in comp.lang.smalltalk:

 

perform: selector withArguments: anArray startingAbove: aBehavior
     "Send the receiver the message indicated by the arguments, starting
      the lookup in the superclass of aBehavior. The argument selector is
      the selector of the message. The arguments of the message are the
      elements of anArray.  Invoke messageNotUnderstood: if the selector
      is not understood by the receiver.  Fail the primitive if aBehavior
      is not the class of anObject or any of its superclasses, or if
      anArray is not an Array with the same number of elements as the
      number of arguments expected by the looked-up method."

        
        ^self primitiveFailed 

So to test that out, I defined a small hierarchy:

 

Object
	Grandpa
	       Dad
	           Son

Each implements a method #foo, which prints to Transcript, telling me who got executed. So, I ran these in a workspace:

 
son := Son new.
son foo

son  perform: #foo withArguments: #() startingAbove: Son.
son  perform: #foo withArguments: #() startingAbove: Dad

As expected, the first prints the result from class Son. The second executes the one from class Dad, while the last line executes the one from class Grandpa. Kind of neat, but this is definitely a dangerous hack to rely on - especially if your runtime can have new classes inserted into a hierarchy via dynamic updates.

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