Each stage of the "System" overlaps to the next, but the first stage, information, overlaps them all.

Each of the features are to be considered each time and not put in to action one after the other out of habit.

The stages of the system are not fixed, you may need to add, for example, more mirror checks or re-adjust your plan as you go through, as new information is received.

Reading it may seem long-winded, but in practice it is simple, quick and necessary.

An easy way to remember it by the mnemonic "IPSGA", practising it time and again will make it almost instinctive.

By driving to the system you will be able to handle every situation in a safe, controlled manner, you will be ready for the unexpected as well as not surprising other road users by any erratic manoeuvres.