You're on the right track :)

See - this sub can be called by any method so I need to make sure everytime it's called I either shift off the package/class info or do nothing.

My orgional code to do this (shift if ref $_[0] or $_[0] =~ /^PKG/;) doesn't work when your calling the sub by its fully-qualified "Package::method" name and $_[0] happens to be a hash ref.

So maybe this will help in understanding my problem:

shift if (ref $_[0] and $_[0]-is-the-ojbect-itself,-not-a-normal-hash-ref) or $_[0] =~ /^PKG/;