These are traditional notions of radio advertising that make a lot of sense on the surface, however what we find over and over again is that people somehow figure out a way to write down or remember a phone number in radio ads. In fact, we've built our business on that. 

Also, as to the question of reach and frequency, we've tested many different configurations on many different campaigns. The results show that the optimum combination varies by campaign - actually by ad. Ads with more focused messaging that is resonating big will produce more profit with greater reach. More mature campaigns or less distinct benefits need more frequency.