@djeddleman had two BMP180 development boards in his stash of stuff. He was kind enough to hook them up to one of the older generation pitot tubes we designed that used tubes still, and take some measurements.
The results were far less than promising.
We saw basically no deviation in the pressure differential read by the two sensors at flow rates of up to 3m/sec, and a static offset greater than that 'signal' by like 5 meters of an air column. That is outside the spec for even these. The new sensors are an order of magnitude more sensitive, but 10x nothing is still nothing.
I can only hope that perhaps one or both of the sensors was plugged or damaged during testing at this point. There was RTV involved, so it is a possibility and would explain the static offset.
@Steven.Carr plans on attempting to etch a board tomorrow to try the same test with our BMP388 boards, and hopefully have better results. The pads are truly tiny though for these devices, so... wish him luck.