Why do people insist on cutting the gills themselves? They bleed well for about 5 seconds before the blood coagulates and clots everything, stopping the flow.
Cut the jugular right in front of the heart and the heart will literally shoot blood 3 feet out. When cut that way, the heart will pump all blood out of the body in a matter of 10-15 seconds.
This also makes it so much easier to clean the fish because the gills don't come out in pieces, just one nice clump of gills.
If its cool and I have access to cold saltwater, I bleed in the saltwater (which also helps facilitate bleeding and keeps blood from coagulating), and then gut/gill as soon as possible and into an ice/saltwater mix.
If I'm in a river, I bleed on a stringer and then clean immediately and into ice in the cooler.
A properly bled fish that is cleaned and iced immediately is 1000 times the table fare that an un-bled fish laying on the beach, or even in the water is.