Smurf,
To a certain extent what you say about safety ladder use is correct, but if you ask your local hospital about ladder accidents you will find that many ladder accidents involve people with years of experience with ladders.
Many accidents have been found to involve heart murmurs, fainting, blood pressure, sudden onset of atrial fibrillation (it causes dizziness), seizures (fits), even the onset of flue or a heavy cold etc.. so anything to minimise the use of ladders is universally accepted as a positive move.
I think that if your customers understood the consequences of vicarious liability, their household insurers might have second thoughts about your ladder useage.