Hickey will still have final say over the 53 man roster but.....Hickey and Philbin are very likely working for their jobs next year while Tannenbaum is not. Lets says a trade offer comes along that will bring the Dolphins a decent future draft pick. Lets say the player that is wanted in that trade is Cameron Wake. Hickey and Philbin are not likely going to be on board with any trade like that because they must be able to field the best team possible next year while Tannenbaum might be working with an eye on the future.
Tannenbaum does have the power to overrule and could make the trade against the wishes of Hickey and/or Philbin. This is all hypothetical but something that could happen with the power structure the way it is. Who really knows what Ross has in mind. So far he has proven to be clueless when it comes to running a football team.