In this specific example you might want the flexibility to transfer to AC -or- NH because AC used zone based redemption charts while NH uses distance based charts. More generally, you are better off with multiple transfer partners in the same alliance because airlines change their programs and the reward you want may be repriced when UA
devalues to match their competitors.
Indeed, it is ironic to read threads extolling the superiority of Mileage Plus after years of complaints about StarNet blocking
.
All true. For example, right now, Aeroplan is offering pretty significant discounts on award redemptions. Coupled with the current Amex transfer bonuses, you can get some smoking deals right now. If I were looking for an award right now, I would much rather have the ability to transfer to Aeroplan, notwithstanding the surcharge. Tomorrow, it might be UA. Next month it might be ANA. To have concentrated in UR right now to the exclusion of Amex would leave you on the outside looking in of the Aeroplan promo.
The recent changes to Avois and Aeroplan, to be sure, have taken away some of the lustre of MR, but just as quickly as that happened, it can quickly go the other way. Some people have tens of thousands of dollars in spend every month and so can build up balances in MR or UR very very quickly if needed. For the rest of us, diversification is a good thing IMO, and anyone who advocates one of the programs at the exclusion of the other might be doing you a disservice. If your accumulation is such that you must choose and concentrate on one of the two, you have to make a judgment on how likely things are to remain static. I don't think Amex is going anywhere on their charge card loyalty programs, and I also think airlines have not been hesitant lately to make substantial changes on very short notice. While UR might be ahead by a nose at this point, I don't think Amex is just going to go away.