Understanding 'the defaultStack'

[Jeanne A. E. DeVoto]

At 4:42 PM -0400 10/9/2016, Paul Dupuis wrote:
>Some long time ago, someone on this list suggested a control block such
>as "using <objectReference>" ... "end using"
>
>Where any object references in the block would always be evaluated
>relative to the object referred to in the start of the using block.
>So:
>
>using card 3 of stack "X"
>   put the label of btn "A" into myVar
>   ...
>end using
>
>Would look for button "A" on card 3 of stack "X"


How should this work for subroutines? Should the "using" scope also 
propagate to any handlers called from within the block?

   on mouseUp
     using stack "My Stack"
       answer field 1 of card 2 -- of stack "My Stack"
       doSomethingElse
     end using
   end mouseUp

   -- maybe in another object's script:
   on doSomethingElse
      answer field 2 of card 2 -- of My Stack? Or the current defaultStack?
   end doSomethingElse


I'm inclined to think that anything that's called from within a 
"using" block should use that scope in turn.