Airliners.net Airbus V Boeing usual nonsense perhaps?

Surely, in my limited knowledge of engineering projects, facts/figures would have been finalised long before the aircraft reach the customer, and indeed that if there was a problem (test flights anyone?) then the customer would reject the aircraft at either the initial proposition stage, or during acceptance flights?

Well, in an ideal world perhaps.

There have been several cases where an airline that have received an aircraft and once in service found them to not quite live up to what the Manufacturer said they would. I won’t name types or any such. Suffice to say, every manufacturer gets it wrong from time to time.