I thought that was 'trawling' ?

I've noticed a lot of people misuse the term 'troll' simply when they don't agree with a statement. OP's statement was fair if you ask me.

You know I must have been half asleep actually fully asleep when I said trolling is fishing, you are dead right its trawling for fishing, DOH!, but as far as I understand it, that is where the term troll is from, a quick wiki search (so it may or may not be correct) mentions "The verb troll originates from Old French troller, a hunting term."

I think this quote from a site called UrbanBaby somes it up pretty well though,

"Ah, yes. Fishing! When you put your line in the water and drag it along to bait fish. Combine that with the Norse legend and you have a nasty person who drags bait in front of others (nasty comments) to see if they'll bite (get angry)."
http://www.urbanbaby.com/talk/posts/53003398