[aerohead]

I looked all the links. Here are some observations:
1) Sal's rocket, at 470-mph, would be governed by transonic flow, and shockwave drag, in comparison to road vehicles, governed by pressure drag due to flow separation ( the SPACE-X Dragon system experiences highest drag at 'Max-Q', with a vehicle of 135-sq-ft frontal area, @ an altitude of about 52,800-feet, negative 70-F, velocity of 1,000-mph, and air density @ about 15% that of air at sea level ).
2) Sal writes that his method is good for 'any fluid', but then he walks it back with the caveat, ' so long as it's turbulent.'
-------------------------------------------------------------------------------------
3) Road vehicles are not designed for 'turbulent' air.
4) Sal reports that Al Unser Jr.'s Mustang ( and I'm presuming that he's referring to a NASCAR Cup, race car ) demonstrated a minimum, 25% drag reduction.
5) At 200-mph, the Mustang's aerodynamic road load is on the order of 540.1-horsepower.
* Surface friction drag power absorption is approx. 36-horsepower ( 6.6% of total )
* Pressure and induced-drag power absorption is approx. 504.1-horsepower ( 93.3% of total ).
* It's hard to reconcile a total drag reduction of 25%, via reduced surface friction drag, when it was less than 7% to begin with.
--------------------------------------------------------------------------------------
6) The Mustang is 193.4-inches in length ( 16.1-feet ).
7) The Mustang is 78.6-inches in width ( 6.55-feet ).
8) The 'top' of the Mustang has approx. 105.5-sq-ft of surface area, compared to an overall wetted surface area of approx. 220-sq-ft.
9) If 'dimpling' the hood impacted the entire 'top' of the car, this would constitute 47.7% of total surface area, or, 3.17% of total drag.
--------------------------------------------------------------------------------------
10) At 3.17-mph, the Mustang begins transitioning from laminar boundary-layer ( LBL ), to turbulent boundary-layer ( TBL ).
11) By 10-mph, Reynolds number is over 1.5-million, with full TBL, and the Mustang's drag coefficient is essentially 'fixed', with the exception of variable wheel ventilation drag, up to 250-mph.
--------------------------------------------------------------------------------------
12) With TBL, and in a most favorable pressure gradient, there's no issue with 'attached' flow over the hood/bonnet, as the TBL is moving from 'high' to 'low' pressure ( Bernoulli Theorem ). As far as attachment ( which is the most critical criteria for 'aerodynamics') the flow doesn't require any 'help'.
--------------------------------------------------------------------------------------
13) Since no data is presented from:
* Gene Haas Racing Wind Tunnel, North Carolina
* Automotive Center for Excellence ( ACE ) Wind Tunnel, Oshawa, Canada
* (Stellantis ) Chrysler Aero Acoustic Wind Tunnel, Michigan
it may be that the drag data presented, is from the CFD evaluations done by Graham Monroe, at The University of New Mexico. If so, we have no data with regards to the software used ( Exa POWERFLOW, and SIEMENS Star CCM+ would be the only 'industry-quality' CFD in existence at the time ).
--------------------------------------------------------------------------------------
Perhaps there'll be additional reporting, with higher specificity in the future.