WOW farming question?

I have cata, and trying to farm in Twilight or deepholm is hit or miss most of the time. There's a guy who used to be in my guild that would get like 3 nodes a minute. How did he get that much? The only tip I've ever heard was to zoom your map all the way out and then zoom in 2 clicks. And a lot of times when I'm farming a node won't pop up on my gatherer map until after I've passed it. Why is that? Shouldn't be my computer cuz I just have a phenom ibuypower computer with more memory and stuff than I know what to do with. Also shouldn't be my internet because I have comcast cable modem so internet. Any help would be greatly appreciated. Thanks in advance!