This is just TITS isn't it? A zombie resurected from the 80s which looked brilliant in the simulator by having more predictable (=inflexible) flow through the sectors to increase the airspace capacity. Wasn't it was shelved when they realised that the UK sometimes gets weather and when aircraft can't fly in the standard tunnel the whole system falls down. There is no improvement to runway capacity or final approach spacing.
TITS for those too young to know was Tunnels in the Sky