White King=Oil=Flavor , Don't let the color of the meat fool ya! True Ivory Kings rule! and are worth twice as much per pound imo
I'm right there with ya!
Back when I was spending a lot of time in BC fishing the locals would call the Ivories "Tyee" and the Red "Chinook". Quite often I would be approached by a local asking, "I'll trade you my tyee for your chinook." If both were bright fish I would always take them up on that trade. Only winter steel and dollies are better eating IMO.
They are really cool coming out of the mid to upper river emerald green and gold. Never seen a red meat fish turn that color. I also think they fight a little harder too 
Not saying your wrong Rad, and maybe were you were fishing they did. But I want to clarify thats not the norm at all in BC fisheries.
Canadians rarely ever call Kings anything but "Springs". And Tyee is any fish 30 pounds or better. Ive fished Queen Charroletts to Victoria and all haunts in between for 25 years plus and have never heard that designation from any Canuck.
On another note those big white Kings from the Frazier are not considered good table fair and are considered trash but are typically huge and fun to fight.
Why one run of Salmon can be predominatly white fleshed is due to genetics as typically white fleshed Salmon is common in about one and twenty fish. The red color comes from the krill that the Salmon eat. But 1 in 20 or so cant process the color from the krill and basically poop it out rather than absorb it into there meat causing the red color. This is the same red pigment that turns shellfish red after cooking.