I find myself agreeing with Howard on this one (also Kev ref the makeup)
It's all a matter of programming yourself to use the side mirrors correctly and adjust them to give the best overall visibility.
It may even be that it's a safer bet in many instances as it will stop the lazy, quick glance in the central mirror with its inherent poor all round visibility and then manoeuvring without a clear picture of what is going on outside that mirrors field of view.
I've tried it by covering it up and it was surprising how quickly one gets used to using the side mirrors. Much the same as when I drive vans.
I have the rod mirror in the centre and it does restrict visibility quite a bit on tighter left hand bends unless you alter your head position.
