IMO - The direction set by Sam Walsh will be critical to developments at OT and TRQ going forward and this could be a good thing when compared to the past situation with Albanese. Albanese after 2 or more really bad deals had is hands tied as to what he could do, was IMO very gun shy and very adverse to any risk going forward. This resulted in the current situation with TRQ where we basically have on going controversy with the GOM and any movement on the deal making side seemed to be non existent. Sam Walsh on the other had has manages Rio Tintos biggest and most successful division through a large grow spurt and although quite aware of Albanese's failings should be far from gun shy. I expect that when he feels the timing is right, Walsh may just have the balls to take a run at the rest of TRQ. (This something Albanese seemed to lack). The question of course is when will the timing be right? Here, I expect that the biggest key is to come to a final understanding or at least a stable state with the GOM.
The biggest reason for Rio Tinto not taking a run at TRQ to date other than what is mentioned above is the political risk posed by the GOM. Once the feel that this has stablized, then there are many reasons why it makes sense for Tinto to either take out the rest of TRQ or to bring in a partner to do so. Every thing from accounting to being part of the sollution in how they deal with the GOM comes into play here. It basically gives them a lot more flexibility and allows for a lot less transparency when TRQ is not a public company.
Walsh is coming in with lots of success and no baggage and so he has a lot more flexibility in what he does than Albanese had.