Thank you for making us aware of this option - I never knew it existed.
My question is, if I transfer points from an account that does not have a premier card account associated with it to an account that DOES have a premier card account on it, will I be able to redeem the points for travel with 25% off? This would make the points in the non-premier account more valuable, if it could be done so effortlessly when ready to redeem.
ThankYou now allows transfers, but the points expire 90 days after which means you should not transfer until ready to redeem:
https://www.thankyou.com/transferPoints.jspx
In the USA, there is no published provision to transfer points or combine American Express Membership Rewards accounts, but you may find a customer service agent who will do this for you on an exception basis.