AW has said you need 4 or 5 different aircraft to be diversified. A 50 50 split would accomplish nothing accept add cost. He said it isnt worth it. Dont shoot the messanger thats just what AW mentioned. UAL mentioned it should be able to handle the grounding with minimal impact with other fleets. Saying about 60 canceleations per day until rectified. A 50 50 here would still be over 2000 canceled.