Sketching for 3D printing

Pen and paper sketching can be a standalone ideation tool but to take the idea further, say in the form of a 3D physical object the freehand sketch would have to be translated into a sketch model using a range of materials such as card, plastic, wood or clay. Alternatively, in the the digital era, the 2D pen and paper sketch would be converted into a 3D physical object using 3D printing, that is, the pen and paper sketch would be scanned or photographed, or produced on a digital drawing tablet, and imported into Photoshop, converted into a 3D digital model using CAD and then imported as an STL file to be dowloaded  for 3D printing using ABS filament plastics, the most used 3D printing material for models. How would the two ideation processes, that is, working in the analogue or digital mode respectively, compare in terms of tool skills or time consumed? Do the chosen ideation tools, analogue or digital, impact on the ideation process and if so, how? For example, do analogue ideation tools such as freehand sketching or physical sketch modelling afford more creative stimulation? Or, does the use of digital tools suggest a more linear ideation process with less scope or encouragement for iteration or improvisation? And what about hybrid ideation modes? Discuss.