Model Forms n 91
Tool Support
A final word on tool support for model creation—if the selection of the correct
model form is necessary to the success of the model, then the correct selection of
tools is necessary for model maintenance. A hand-drawn model can be accurate,
concise, and correct, but it will be very difficult to incorporate modifications over
time. Consider the cost of blueprint drafting before the invention of CAD (com-
puter-aided design) systems. Any change required the complete redrawing of the
model view (the blueprint). is was time-consuming, and it encouraged errors to
creep into the diagram, which required careful review and checking. However, a
tool is only as good as the skill of the operator. Someone lacking in modeling ...