Its back to the future....
The original imagehandler created images that way using the image name and _med or _lrg.
Then a BETTER way was found using the bmz functions and the hash.
Download the older version, if you can find it for inspiration.
imo: Personally you are wasting your time as lots of improvements have been made since.
Lots of debate about this.
Majority opinion seems to be its irrelevant