You really should start your own thread, not just start off on another tangent. There are lots of other guys who may be experiencing the same problem, or may have this problem in the future and can locate an answer using the search feature. That way I can concentrate on problems for which the search feature came up empty. Have you tried the search feature?
My opinion on your problem (see, I'm abrasive BUT helpful!) would lead me to doing the test on the system. You say the system does work, just surges, so in my opinion, the test results would be inconclusive, meaning everything will probably pass just fine. In about 90% of these cases, by my own estimation, the control unit, also referred to as the cruise amplifier, will repair the problem, with the slight (10%) chance that it may be the actuator.