I like the explanations everyone has give here. I have never used 2-point perspective so thought this was very informative. Maybe a little off topic but I like to use the parallel view when aligning things (at least for the type of models I do) but then I switch to perspective mode when doing everything else. I just find it a little easier (for me) to do the alignments in parallel especially when I have components with subcomponents.

@Jean That is writed v6 but it is in fact v8 so the suspense is total for me @Jeff Maybe you must multiply scale by 10 000 then make the rotation for win some decimal?