+1 for post #369 .. should be compulsory reading for all engineering undergraduates ...
As for the "friendly little molecules" that separate at the leading edge, and are miraculously re-united at the training edge, having had many adventure in-between, how many students have been taught that over the years.
I'm presuming that Leadie is being a tad tongue-in-cheek.
However, one hopes that any newchums reading this thread are comfortable with the notion that the truth of the matter includes some extra words -
that don't separate at the leading edge
and are miraculously not re-united at the training edge
how many students, incorrectly, have been taught that over the years.
As to being re-united at the training edge that just doesn't happen and the fact that it doesn't happen is fundamental to lift production.
While I'm on the soap-box, the old nonsense about parcels of air separating up at the front and then joining up at the back ... is, likewise, nonsense. Just doesn't happen .. the bits going over the top win the race handsomely.