Zero tolerance for out-of-scope references!

Hi Steven,
Here is a question that I have been pondering for sometime and haven't found a definitive answer to.  Perhaps you can shed some light.

When writing a procedure in PL/SQL, I pass it all the variables that it needs to do it's job.  Of course, it has access to any variables that are defined at the global level - but I rarely if ever use these (perhaps a few constants here and there). 

However, if I have a procedure that has a couple nested sub-procedures - should I follow the same pattern as, above?  It seems a bit silly to pass parameters to a proc and then re-pass those same parameters to a nested sub-proc when that nested sub-proc already has the variables in scope. 

So should the rule of thumb be: 

For procedures, pass all parameters in or use local variables as needed. Use global variables only in extraordinary circumstances. 

or 

For nested sub-procedures, don't pass variables in or out.  Use what is already in scope in the outer procedure. Only pass parameters to nested sub-procedures for special situations.  

Thanks in advance, Alan

NEVER code out-of-scope references in your subprograms. Use the parameter list to pass in and out any variables that are declared outside that subprogram.