Well , I think you could safely say that  its better to process your catch asap . Leaving them to pickle in their own guts  for a night wont render them inedible  but you gotta think that they could have been better .

Yep agree with Keith if you put the KY on ice to quickly after you have cut through their throat they won’t bleed out properly. Bleed them as soon as they come in to the boat while they are still pumped up after the fight.

KY do taste a lot different to snapper

Well I just figure you wouldnt ( I wouldnt ) leave a pig , deer, sheep , cow  or poultry so why leave the fish if you dont have to 

You guys are all going to laugh but I reckon fish keep best ungutted in a cold fridge. I recently left a snapper whole , ungutted in the super cold tray of the fridge for 10 days . The fillets were perfect , with the flesh still firm and translucent , no bad odours and tasted good. As soon as you cut the flesh it is opening it up to bacteria . I'm sure fillets would not have kept so long . Of course some fish , like gurnard, trevally and kahawai etc don't keep well at all, just a few days. 

Commercially caught fish,be it trawl or longline ,arent gutted straight away and before you say they taste bad,its not fish markets fault,its the way they are treated in the supermarket. Buy from a proper seafood market with high turn over and fish is perfect,buy from a supermarket and flabby/grey/eyes sunk because they leave them in chilly bins till reguired,basically no idea.

My understanding is that guts left in is fine for even a few days if the fish is kept at a temperature just above freezing (i.e. salt ice slurry). Anything else and I would want the guts out ASAP. 

When I was bleeding gemfish recently, I found a big artery underneath the gills. When cut, blood just hosed out. Looking at fish anatomy diagrams, I believe it to be the ventral aorta. I'm going to look for it in other species next time I'm out.