Crabman
You mention flat plates. I agree with you of course. For my students who cannot understand how a flat plate can ever produce low pressure above its top surface I talk along these lines:
Aero guys call the streamline that defines the boundary between the air which goes over a wing from the air which goes under a wing the ‘stagnation streamline’ and call the point where it hits the aerofoil the stagnation point.
The key thing to realise is that the only time the stagnation point (SP) is located right on the front of the wing leading edge is when the wing is at such an alpha that it is producing zero lift. If the wing, even a flat plate, is at an alpha that allows lift to be produced, the SP will be located on the underneath of the wing a small distance back from the leading edge. Furthermore the SP moves steadily back under the wing as alpha is increased until the stall – and even beyond. This effect can be seen in any simple wind tunnel where smoke is introduced to enable the flow past the wing to be visualised.
If you don't have a wind tunnel and to understand how this can also happen with a flat plate, I offer the following explanation. Imagine it is a windy day and you are carrying a large 8 x 4 ft sheet of chipboard out from the DIY store to your pickup. Being bright you take care to hold it flat and edge on to the wind so naturally the SP is right on the leading edge and all is well. Then out of the corner of your eye you see another chap who is carrying his sheet flat on to the wind.
Here the SP is right in the middle of the board with the air spilling round all four sides. He realises your way is easier and starts to rotate his board towards the flat position you used.
As the alpha is reduced from his 90° to your 0°, the SP has to move forward from the centre to the leading edge. Therefore is it not reasonable to accept that as the alpha of the sheet is reducing through say 10° (below that for the stall but not yet zero), the SP will be well on its way to the leading edge but it will not actually get there until the alpha for zero lift is reached? I apologise for that childishly simple analogy but I find such things useful so perhaps others will as well.