I came across some articles suggesting you switch the ad display option to "rotate" instead of the default "optimize" in order to test ads.
While they suggest leaving it until each ad has X amount of clicks, I'm wondering should you switch back to "optimize" once you have found the top performing ad, and put in some more variations of it?
Or should you weed out the bad adcopy, but leave the campaign set continuously to "rotate" and just keep testing adcopy, and deleting the bad copy....
or you can let G do the testing and figuring out which ad is best to show by selecting optimize.
so there's all kinds of right answers.
most often, but certainly not always, i set it to optimize and occasionally delete the ads that are failing to get shown (G is rating them as poor) and i keep adding new ads to the mix to see if i can improve further. continual optimization.
I'm going to try it for a week on a few campaigns to see what happens..