Thanks Anomolous, point noted. I should also reflect that it is not truly the map operator that is using the $#arr construct to obtain the highest array index as such, rather it is being used by the .. range operator. As map expects a list of some description to work with after the modifiying operation. In this case we give the list in scalar context of a range, much like the for iterator, so perl goes ah yah, this is some funky for loop right, and cooly proceeds.
I will now look into how the $ARRAY_BASE special variable affects the $# variable. I would not have thought a difference would be made, being as the highest index of an array is always going to be the highest index? (unless $[ is set higher perhaps... hmm...).
*Footsteps echo quietly away as Coyote trundles off into the dark echoing corridors of the echosome vaults.