@PILOU

And that's exactly the point! Not many artists and designer happen to be rocket scientists and many of them are still looking back at their math class at school in sheer horror! ;)
Also 'creative folks' do not always like to read through manuals, faq's or forums like this one, even though it would help them without a doubt.

I do appreciate your detailed explanation and examples about the capabilities of MoI to process formulas, yet this way of finding any 'point of interest' for proportion or distribution
simply interrupts any free flow of sketching and will probably overstrain the majority of people who think mainly in their right brain hemisphere... ;)

Working with MoI I really like just because of its beautiful design in terms of simplification and I assume it is designed this way for all of those creative people who do not own
any degree in engineering or science and do not intend to get one just to operate their 3D design software somewhat properly.

I just started to look into Rhino for Mac and it became quite clear already how much more thought was implemented in MoI to get a good visual result from brain to screen intuitively.

Maintaining simplicity while keeping full functionality is a challange for any good programming design and takes probably a good portion of the overall development time.

For now you got me interested in using MoI for a calculator so I will practice your examples, but only because I recall that tan() got not much to do with some leasure time at the beach ... ;)