In my view it is enough to focus the mind of a Premiership millionaire, without being excessive. Now departed, but Danny Guthrie would have been chomping at the bit at a bonus scheme like that; he could treble his wages for goodness sake!
The latest hurdle put forward on the Mathieu Debuchy transfer saga is that as well as an £8m fee, Lille are insisting on possible bonuses such as sell-on fees and image rights.