Not a lot of benifit in churning:
e.g. AA to HHonors:
- 25K AA miles becomes 50K Hhonors points @1:2,
- 50K HHonors points becomes 7.5K AA Miles at 10000:1500
...
So Churning 100K AA miles:
- 100K AA->200K HH
- 200K HH-> 30K AA (Nett 130K AA)
- 30K AA-> 60K HH
- 60K HH-> 7½K AA (Nett 137½K AA)
- 7½K AA-> 15K HH
- 15K HH-> 2¼K AA (Nett 139¾K AA)
(NB non-elite status AAdvantage members must have a minimum available mileage balance of 25,000 miles in order to complete a transaction)
Also, each AA->HH transfer costs $30.