The Automated Mathematician (AM) of Douglas Lenat has discovered a very useful way of generalising concepts which is applicable in many circumstances: If a concept is expressed as a conjunction of two or more other concepts, try to examine the new concept built by replacing the conjunction with a disjunction. The application of this heuristic has allowed AM to discover the concept of "prime number". Applied to the description of a complex system, this rule of thumb may be interpreted as: replace an exhaustive and sequential presentation of a complex system with a set of short views on that system.
The development of an oil or gas field may require many tens of wells. External conditions may imply that well heads have to be clusterised to decrease the financial investment, as for instance in the offshore oil recovery, in the Artic or in marshy areas. Clustering of development wells may also occur to minimize pollution or noise as for example in urban areas or tourist regions. In that case of well clustering, most of the wells have to be inclined in order to reach distant targets. Directional Drilling is the particular technique which allows bore holes to be deviated from their initial inclination (see figure 1). As most projects must be conducted, a deviated well project is decomposed into three steps: planning, execution and evaluation. Even if in other areas, post analysis is often neglected, in well boring this phase is of considerable importance since the behavior of drill strings in function of geological formations is unknown until wells are drilled.