Take a look at the steady throttle parts of this log.. The spark gets erratic as does the feeling of the car.. It seems like its activated by map transients.. Looking at it closer.. it the spark "zig-zags" only happen above 3000rpm.. which is.. the dyn airflow disable point (shouldn't make a difference, I'm in SD). Actually, its pretty consistent.. Check it out.. Why would dyn air disable make a difference with a 2bar SD tune?

http://home.comcast.net/~edward.savides/ve6c.hpl
http://home.comcast.net/~edward.savides/turbove6c.hpt