Stop thinking like a Marketer.. you must *be* the Consumer.
Here is what I mean by this.
Say you are promoting a product. You need to stop thinking like the person trying to sell it. “dog training” is a nice general keyword, but really your keyword should solve a problem. “stop dog peeing on carpet” is a person looking for a solution. The people looking for solutions are going to be much more interested in your dog training guide. This concept can apply to just about any niche.
Here is another one
auto insurance quotes vs i need insurance vs i hate geico
look, “i hate geico” has zero ads right now. Bet you get some killer CTR and conversions with links to someone who isn’t geico 
But how do you know which will work and which don’t? Easy. Do all of them. Yes *all* of them. (caveman speak:Turn off bad. Leave on good)
I can relate this post to the one you posted about high CTR at lower positions. I never did aff marketing but I did check some ads as well as search content several pages down. It could be some long tail or some specific key words on your ad that would have attracted more clicks.
I could be wrong on this , if I am appreciate you can clarify more on this if this is a general trend ……
so easy, a caveman can do it
This just goes to show how important keyword research is. It truly can mean 10 visitors a day vs 1000 visitors a day.
Thanks for the killer reminder- sometimes I forget to shift my thought process.