The mini switches are not a coil split. Otherwise, there would be no claim of hybridism with a 408. It would be a plain old coil split like the 513 single coil modes with the resulting loss in volume between it and Modern Humbucking mode. The claim of 408 heritage means it's coil stealing for the single coil sounds. It's taking turns from the passive coil and adding that to the active coil. Furthermore, I think that's backed up by my observations that the mini-switches on my 509 are wired up exactly like my Siggy, and my two 408's. Typically, PRS coil splits through mini switches are two wire affairs(i.e. tap wire, ground wire). These are full four wire jobs like the 408 which are feeding a 5-way instead of a 3 way. And, there is no loss in volume between singlecoil and humbucking tones which was the big selling point of the 408 if you recall. That seems to point to the 509 being a true hybrid between a 408 and a 513.
