It mirrors exactly the helmet argument from medical endorsement through the "Thudguard saved my child's life" anecdotes and the emotional blackmail of "unless your child wears one of these they will become a vegetable"
Yet people who unequivocally accept those arguments for cycle helmets repudiate the same criteria for this (apparently very silly) protective equipment
After all to quote the head of the Accident and Emergency Doctors "Professional body":
It is a pleasure to support the 'Thudguard' in my capacity as President of the British Association for Accident and Emergency Medicine. Any device which helps to reduce the number of head injuries sustained by young children each year is most welcome
British Association for Accident and Emergency Medicine