Now, that by itself justifies becoming involved early. However, where eXpress uniquely addresses this, is the fact that eXpress will help the engineer maintain their investment into these early models built for early trade-offs and analyses. As failure modes become more apparent, and as lower levels are built, the initial model and testing philosophy can be transitioned over to incorporating failure modes as the predominant element that the model uses. The functions drop down to forming the fabric, but no longer act as the element of highest concern. This transition would normally require an entirely new model to be built in the case of spreadsheets, or other modeling tools with the exception of eXpress. Even math models and similar approaches would require a complete rethought of the model. eXpress, however, allows test definitions to be changed piece-meal as failure modes pop up for any of the covered objects. Tests themselves can be hybrid, of course, just as the model can be.It is this transition that maintains the investment into the model that justifies becoming involved early, since the model will “see the engineer through” from the original thoughts to the final diagnostic design. This avoids a double-hit for modeling, the possible introduction of errors when the model is rebuilt again. In addition, one of the most dangerous things that can occur is that the final design can completely diverge from the original concept. eXpress solves this problem by using a hybrid model which allows the original model to mature and evolve throughout the design phase by maintaining a single modeling environment. Without the capability to develop hybrid models, multiple models must be created as the design changes. Normally two or more different models are not easily compared to ensure the original concept has been maintained. Although different departments all try to maintain the concept, they are themselves often working to different specifications. eXpress becomes the only tool looking across the disciplines from a system perspective as the design matures through the entire development cycle.
Reference: Thomsen, Erik. 2002. OLAP Solutions, Building Multidimensional Information Systems, Second Edition, New York, NY. John Wiley & Sons, Inc. ISBN 0-471-40030-0