Know how to estimate the value of elements both personally or representatively and to the other party.
One way of estimating the value of components is to consider the proportional role that a component or element plays in the whole and whether the element is a critical feature of the whole. Another way is to attempt to establish a value attributed to the element by the other party by the way they react when certain statements are made about the element.
The knowledge named 'value component parts' is considered to be very important.
In addition, the knowledge is thought to be quite complex and difficult to learn, it is learned mainly by experience but needs study, and is specialised knowledge.
Opinion is that it is quite justifiable knowledge.