Alf ... if, by going around in circles, the message eventually becomes clear ... then that is probably a reasonable thing .. ? .. and I concur with your thoughts entirely ..
(a) one does the sums with one's aerodynamicist hat on in the back room
(b) one confirms a range of things in the tunnel
(c) one goes out and flies the climbs to find just where the optimum configuration etc lies
(d) one considers what is a reasonable compromise considering the numbers, workload, etc., etc.