I can only blow 350 on the peak flow
An initial JAR class 1 at Gatwick would be seriously in doubt if a
candidate could not manage a PEFR greater than 350 l/min.
Just imagine a temporary WORSENING of that, for whatever reason at
all, and then combine that with the reduced oxygen content of a cabin at the equivalent of 8000 feet.
Still capable of dealing with any in-flight emergencies ? I don't think so.