Increasing petrol duty and abolishing the RFL would help reduce pollution, but more importantly it would do away with all the costs of issuing and printing RFLs and the cost of enforcement, fines and their collection.
As a JP I know how much time the police and courts spend on finding, arresting, prosecuting and convicting those who do not have a valid RFL and often the additional costs of collecting (and often never collecting) fines that are not paid immediately.
THe RFL leads to extensive, unnecessary work which is a complete waste of time and effort, as the loss in revenue could be added to petrol tax and all the costs related to RFL could be saved.