I have done it off and on the past 3 years, and as recent as the last month. If your MR account is set up for online access it's a breeze. Just make sure the ff account is not linked to someone else's MR acccount if it is they will have to delink it first. If you sign in online to your amex card which automatically pulls up my MR info. You can link someone's ff account, transfer points then delink their account in a matter of minutes the transfer is instant. When I mention delinking, what I mean is say your brother has an amex card and gave you some MR points, then your dad could not give you more if your ff account was linked to your brothers MR account. He would have to log on or call and delink it first. I assure you it will work. I have done it at least 15 times.

Steve