I believe there is still a big debate over the 'correct theory of flight' at the moment (well - since time memorial).. The change of flow direction/downwash camp seems to be in the ascendancy - although the benouli, longer path reduced pressure is still probably the majority. The only main problem with Benouli and the longer path/higher speed flow theory is that it should work for any shape - the most efficient aerofoil should be a semi-circular cross-section. This is obviously not the case so it points to a basic problem with the theory.
My personal opinion is that Bernouli was obviously pretty much correct, however there is a little more to it and downwash/change of flow must also play a part, as without change of flow direction, lift does not appear to work. The exams all point to this change of flow direction as being a critical part of it and that - I believe - is the answer they are expecting. There again - I just learnt the answer they wanted and passed the exam!!
