TAC inop,
...PM should anounce passing 80 kts, and the PF should verify....
Why should he/she announce something that which you both normally expect to see?
British Airways don't invent their own SOPs. BA consults with the manufacturer (Boeing or Airbus) and then decides on the SOP providing this is in agreement with the manufacturer.
At the end of the day, how many times has a B777 aborted take-off because the FMA didn't annunciate 'HOLD' at 80kts eventhough take-off power was correctly set?