I don't think it really would have mattered if your drag was set right or not.LOL!It sounds like that was just one of those rare fish that you just have to tip your hat to for getting the better of you.Nothing wrong with that.If every fish came in easy,it just wouldn't be the same.You will always remember when a fish beats you like that.In fact,it's probably one of the better memories you will have of fish you've hooked.One of my best memories is of hooking a chrome bright chum salmon on the fly.I've never seen a fish fight like it,including steelhead.It jumped 7 times and took me to the end of my backing 5 times.I was running up and down the river bank reeling like crazy one minute,then holding on for dear life the next.In the end,I ended up on my butt in the water and the fish was gone.I couldn't shake the grin from my face for a week.Those are the kind of encouters you remember.The fish won plain and simple,just as it did in your case.Next time maybe it will be your turn.Sounds like you had a beauty on and if it were headed down the fast water,it would have been tough to stop.Don't ya just love fish like that?!