Would you notice a loss of TR thrust at 140 kts in the cruise? The TR can't be at that high a pitch with all the tail boom and vertical fin working for you.
I know the Brit Mil Puma was not brilliant in terms of directional stability but I thought that had been addressed with extra area on the tail on the civil versions.
Is it so bad that you can't achieve any power/speed/sideslip configuration to make a powered approach?