I'll just pick up on the word "criticism" in relation to the above posts because I don't think that they are. What I believe @Courier has done, (and others, including yourself!), is an excellent job to analyse the information to hand, and to identify that within the speed measuring processes there may be inconsistencies that, whilst very small, will affect the total accuracy of the final readings. The higher the speed goes the greater the impact of any inconsistencies and I believe we are still talking about +/- variations, so depending on which side of the fence you wish to make a stand on, the opposite could also be deduced from the same findings.....or you could just sit on the fence and say that the result is somewhere in the middle and we are all none the wiser! I don't think that like for like, anyone will assert that a man with a stopwatch is going to be more accurate than a properly calibrated dynocar. (I'm still hoping to hear if anyone knows how we can be sure of the calibration!). Calling the stopwatch used into question is a little far fetched I think - a timepiece, (and I know nothing of such things), that perhaps looses a few seconds or even a minute over say, a 24 hour period will have such a minute bearing on the outcome as to not warrant consideration. Clearly the reflexes of the man holding the watch deserves the greatest scrutiny as well as the accuracy of the milepost placements!