While there are people in this thread that have basic confusions on the subject of probability, the OP (Darth_Sweets) is certainly not one of them.
He used a type of statistical analysis called a confidence interval, and performed sophisticated math analyzing his raw data. The only disagreement I had with his analysis was the sample size, not his methods or understanding of probability.
Either you didn't actually read the OP, or you didn't understand what he was saying.
While I agree with your general point (perhaps the poster you replied to was referring to another contributor in this thread) - the bolded is a pretty huge problem. OP stated it's "almost impossible that the 20 percent is the true rate of getting a new plan" which is patently ridiculous based on the extremely limited data. I don't care how sophisticated his methods are (I agree he does seem to have a good grasp of the tools involved), but sample size is such a critical factor here that I can't really blame anyone for assuming OP has some gaps in his understanding of probability.
No offense @OP - go ahead and run another few thousand trials, and re-run your analysis. Then we'll talk.