I have one of these, it is great.
It has a twist throttle AND pedals. If you peddle (ie feet going round, no pressure needed) you don't use the throttle at all, max speed under motor power 15mph. But you can also keep the pedals stationary and use the throttle, and this is where the "secret switch" comes in (actually on mine a connector joining two wires that you can disconnect). With the connector disconnected max throttle speed is again 15mph, with it connected it is slower. The third way you can use it is to put your feet up on the footboard once you are in motion, and the pedals will go round on their own, so you don't need to use the pedals or the throttle! (Cuts out when you brake!)
Although it is possible to pedal it, you wouldn't want to - you are not in a good pedalling position, there are no gears, and the thing weighs about 40kg. It is definitely pushing the boundaries of what a bicycle is, but none the worse for that IMO. I feel safer on it than on my push bike - it feels more solid, has mirrors, indicators, a brake light and great headlight, a horn, and full suspension and fat tyres for all the potholes around here. The brakes are better than anything I've ever experienced on a bike - the motor is used in reverse when possible so are very sharp and unaffected by wet, and the mechanical brakes when it needs them are enclosed drum brakes. It is not fast - I have been overtaken by a push bike cyclist before, but also catch up other cyclists occasionally, so about cycling average I suppose.
If you are a young fit cycling enthusiast with all the gear it probably would not interest you. But if you are like me, getting on a bit, have achy joints sometimes, just use a bike to get around locally, it is great for nipping to the local shops or station, and easily patked. I use ordinary cycle locks with it, althoigh it has a remote keyfob and alarm!