A small addition to point #3 (Limitations of Current A/B Testing Softwares): Manual Editing does not work. The only workaround with current softwares is creating a new page for every variation and then splitting the traffic.
Both the topics are quite different, while the other posts is focused on showing how split testing can be done on Adsense, this one points out the major issues faced by publishers when using popular A/B testing tools.