The problem with the AB6 is that if all the window/aisle pairs are gone, the gate agent may decide to stick a couple travelling together in the D/E center combination whether you have a block or not. So if you're going to try this, find a row where the other two seats are both full with actual bodies (not a block on the inside seat).

Whatever you do, avoid the right inside aisle, as the entertainment system for the row goes under the seat. There is minimal legroom on that seat because of the entertainment system, which had me in agony for six hours BOS-LHR. Oh to have had a VIPOW with which to upgrade!!