While it is relatively straightforward to make a qualitative case for hypothesis #1, proving #2 and #3 is more difficult. Providing quantitative measures (#4) is an effective way of demonstrating the validity of all the hypotheses, but is difficult to achieve. The difficulties arise from the following:  No two construction projects are quite alike, either in their physical composition or in the progression of their design and detailing. The lack of predictability of the sequence and timing of decision-making by owners' and/or architects' makes the actual process that transpires for each project unique.  3D modeling is not yet a mature technology for design of building structures, making measurement of complete cases of 'future use' impossible. With the exception of structural steel, it is also not yet an accepted technology for detailing of building structures.  The process of engineering design and detailing is itself likely to be different for 3D modeling than it is for 2D CAD. Comparison is therefore not a simple case of comparing each activity from one set of activities with its equivalent parallel activity from the other set. For a quantitative comparison to have value, it should be made between whole alternative processes. Thus it is not possible to draw a direct comparison between any two identical projects where each is performed using a different one of the two paradigms (2D CAD or 3D modeling).