I recently subscribed to the magazine and received the 2015 pocket price guide and was stunned when I saw that "high" value for a Tii was $31,000 while the high value for a 3.0CS was $30,500. With the latest issue came the 2016 pocket guide with new value categories of median and high sale. They now have the high value for the Tii at $41,800 and the CS at $65,000. It seems likely that they got an earful from coupe owners but something obviously got their attention.
In general my sense of SCM is that they try to keep track of literally everything that is sold at auction and that auction prices are what they focus on, almost entirely. As most of us know, aside from CSLs, most E9s are sold elsewhere and often through word-of-mouth for the really good ones, so Keith Martin's lack of accuracy is understandable.