When Shawn Coyle speaks, we should listen. Many thousands of hours are conducted low level by single engine machines without problems - not just in the USA.
The archaic ruling we have in the UK (which is of course ICAO-based) stems from the time when SEH were regarded as being unreliable - and when twins came along, everyone thought they were the magic bullet.
We have to change this perception - it is badly flawed and is restricting the overall growth of helicopter ops in the UK and elsewhere.
The stats do the job - there is no great problem with singles anymore. And I agree with Shawn - piston engines are super reliable and cheap to operate.
The California forest fires last November - one entire evacuation/observation area was handled by a Police-spec R44. It could stay aloft for 3 hrs and co-ordinate all the stuff on the ground.
Problem is (in the UK) our heli rules and our police/HEMS aviation are all run by ex-services people who just don't have the piston experience. They joined up, put on the suit and were immediately handed a Gaz or some other turbine toy.
Why doesn't the mil in the UK go for low cost training with a fleet of 44s ?? How come they can ignore this in such cash-strapped times ?