411Ayou are wrong! There is no legal in-flight requirement i.e. 60/40.
Have a look in numerous AFM's you will find a landing field length for dispatch and an actual landing field length, the actual landing field length can be used when in-flight.
Also have a look in FAR121, there is no requirement listed.
PS, POI's aren't GODS, they should be open to discussion.
We had an ETOPS restriction placed on us by our POI, we discussed it with Boeing, JAA and researched the FARs, AC's etc. This restriction was unheard of. Another visit to our POI proved that it was his interpretation and wasn't a legal requirement! Needless to say, it is no longer a restriction.
Mutt