It wouldn't.

On every flight I have had delayed, the passengers on board the aircraft have had bags within the correct size/weight allowance. In fact, on the last flight I did before my days off, the bags tagged and placed in the hold were an embarrassment, because the last ones that couldn't be accommodated were tiny!

I think BA Management is just woking up to the real issue, that this is costing us far more money than any short-term competitive advantage we may be having.

Silver or Gold Exeucutrive Cardholders, can and often do, take a minimum of 100 kgs for each family member, of baggage free of charge when travelling economy. 2 pieces of 32kg each in the hold, 1 at 23 kg overhead and a 4/5 kg bag under the seat. The excess baggage revenue we are losing on family Avios redemption bookings is astounding. Many destinations allow a third checked bag.