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there is a zone of air around the trailing surfaces that moves at a significantly slower speed, which is the basis of lift.

This myth -- that the Bernoulli effect is what causes lift -- is so pervasive that even most pilots and geeky engineer types believe it. What actually happens is that the airfoil moves through the air at a slightly nose-up angle causing the air to be directed slightly downwards as it flows by. An "equal and opposite reaction" to the downward flow then occurs in the form of a lifting force. So it's actually an airflow vectoring effect, not Bernoulli, that lifts a plane.

The classical demonstration of the Bernoulli effect is to blow air over a strip of paper and watch as it rises, but actually this disproves the Bernoulli effect and proves the vectoring effect instead! If Bernoulli were the operative mechanism the strip would continue to rise and curl towards your face. But what actually happens is the strip rises till it's almost level and then rises no further. This is because the laminar flow is no longer directed downward, as it was when the paper was drooping, but rather outward and therefore not creating any lift.

That lift is caused by airflow vectoring is why symmetrical airfoils can work. It's also why the Wright brothers wing worked. Their airfoil seen in cross section was a curved line, not a volume-containing curve, so the air above and below the wing travelled the same distance. Since the Bernoulli effect requires the upper and lower flow to travel different distances (and therefore at different speeds), Bernoulli couldn't be what lifted the Wright brothers' aircraft. It actually was vectoring, just as it is on modern aircraft.

Pretty crazy, huh?

Your explanation has made sense to me for a long time, but I think most aero textbooks still talk about "circulation", a concept that involves some pretty heavy math. One weird experience happened to me standing in a parking lot about half a mile from a Love Field runway. A DC-6 or DC-7 passed over on final approach, then about 20 or 30 seconds later there was a very gentle downwash which obviously came off the wings of the airplane. The air happened to be very still so that wind did not break up the downwash before it reached the ground.

I always wondered why Boeing built the B-17 and her sisters with a symmetrical airfoil, while the other heavy lifter of the era, the B-24, had a very advanced airfoil design. And for several reasons, the B-24 did outlift and outrange the B-17, but was more vulnerable to enemy fire.