I keep a bag or two of skinned out smaller cats on hand. Sometimes I get a hankering for some whole fish. I learned to fillet catfish with a regular knife like that but I got an electric one as soon as I could
. I leave the blade in the cut and flip the fillet over with the end of the blade then pop right in against the skin to separate the meat from the skin. IF I cut thru the skin or pull the whole this off of the fish I then come cut in behind the ribs but not thru the skin. After that ichold the ribs and fillet the meat off of the skin backwards using the ribs as a hand hold.