This flaps 2 mandate was a pet peeve of mine, when flying the 'Bus. 2 out of 3 operators I've flown for insisted that we always used F2, only one allowed OPT flaps.
The main reason cited, however was tail clearance on T.O., which was better at higher flap setting. I believe this claim is somewhat valid for longer planes such as A321 and A346. However definitely not in the A320, which has plenty of tail clearance margin. Airbus FCTM is also not very clear about it and suggests using higher flap setting due to tail clearance when possible. I guess they just want to play it safe to avoid litigation.
I was, however, frustrated by this blanket approach. We have several flap settings available for a reason - and we should use them according to situation. Optimize when able, be conservative when conditions dictate. Mandating the use of F2 means that the management don't understand how flaps work in a jest transport and/or are insecure.
A great example of this was a heavy A330. On a long runway, the V2 could be some 20-25KT below Vfe F2. Guess what happened on a windy day - during takeoff in a gust speed would jump towards Vfe and people would pull the stick and over-rotate, at high rate cos they were scared of overspeed. But when I suggested using 1+F the answer was invariably 'noooo, F2 gives better tailstrike clearance'
