DC Rainmaker does not say that the device compensates for changes in position (on the hoods / on the drops), nor for lateral wind; only those together might create inconsistencies of 10-20 % or more in measurements. He only makes some indirect suggestions, to make the reader to self convince that everything is accurate. Subtle (but well known) marketing technique. Furthermore, he says something about some "miraculous" auto healing, suggesting that no matter what, the system will finally be accurate.

I am way above 6 years old, I can't believe in miracles, thus, I don't "buy" it.
But, whether you "buy" those or not, I will not say you are funny. Ha!