While investigating the non-blipper, the mechanic noticed that the front pulley was moving funny. Investigating further he found it worn on the inside, and the shaft worn too.
This bike has only 30000km on it in almost two years. Our thoughts at the moment are that it was damaged during the 25000km when the belt tension was at the (factory mandated) *way* too high setting. Next time you get your Spyder serviced, have them check for this unusual wear. If it appears outside warranty, it will be expensive to have fixed.
Pogo.