Yeah definitely turn it off if you want to test multiple ads to see which one gets a better CTR. Also as RedWolf said, the stronger CTR ad may not convert better, yet it will be shown more just because it gets more clicks, knocking down the other ad that actually produces a better ROI.
RedWolf, I assume you add the string to the url, so they land on www.yoursite.com/ad1 (or 2/whatever), and then track to the final sale to see which ad actually produces a better ROI?
All the Best,
C.K.
AWA, if Google wants to apply its 'Don't be evil' philosophy to ad copy testing, wouldn't it be great for Google to offer a version of ad copy optimization where the ad copy is tested to see which *converts* best for advertisers? This would be a reason for advertisers to use your conversion tracking more often than they currently do, and would better achieve Google's long-term profitability by improving advertisers' ROAS and ultimately increasing their spend.
Heh. Very interesting suggestion, shorebreak, and one that I've heard under discussion here a time or two. I'll pass your feedback on later this week, as a vote to make it happen. ;)
<added> I've just pasted your comment, verbatim, as the very first entry in this weeks report. Thanks! </added>
AWA
I set up an ad group with two ads -- one with almost zero CTR and second with average CTR of about 1,5% -- and let them rotate evenly. And it worked perfectly. My keyword got a little less than 1% CTR, just above the 0.5% disable limit and I did not pay too much for clicks.