Yes, too much timing can cause problems. Execessive advanced timing tends toward higher peak pressure rise. Not sure about our 5. 9s, but the generally accepted value is to stay below 10 bar/degree pressure rise for engine longevity. I know that doesn't help much without having a "timing sensor" or pressure transducer.
I would be curious if someone could put some thoughts together on how total timing may be measured. I know TST has an adjustable timing feature, but from what I understand, it adds a certain number of degrees to the existing timing, and is not used to set timing in an absolute sense. --Eric