Then he stops doing Tests and goes back into first-class cricket and he has to start learning again. It could be dangerous for an umpire's career,' said the former England all-rounder.

He also raised the intriguing possibility that TV technicians responsible for providing the pictures for referred decisions might have to be selected from countries independent of the competing teams.

'If you do use technology, do you have neutral people working the cameras and the systems? I am not suggesting that anybody would be corrupted but you will have to have neutral technicians.'

Willey said to take the pressure off umpires, there should be an increase in the number of Test officials and they should be allowed to stand only in one Test of a series.