Blender was not born on Linux but on SGI and then ported to Linux. The design of the interface of Blender has no connections with Unix, in fact there is no other tool, from Unix or other OS, that has a similar design. Blender was an internal animation tool for a company named NaN (Not  a Number) and the philosophy around the software was to make it one of the most effecient, fast and powerful modelers.

It has been proven by many indipendent tests that menu-based UIs are not the most efficient ways of handling this kind of interaction. Other softwares, like Maya or ZBrush, in fact add a form of context-sensitive interface elements, like the right-click menu of Maya or the popup menu of ZBrush, that are meant to provide tools pertinent to the job right in the place where the artist is focusing, thus minimizing the shift from the work to the UI.

In the field of post-processing software, like After Effects, or Final Cut Pro, keyboard-heavy use is the norm, as editors and compositors need to manage huge amount of data under very tight deadline. This is also determined by the fact that professionals need to spend many hours in front of a compuiter and mouse-heavy UI are know for causing CTS. Many of the post-processing tools, like After Effects, were born on Mac OS or Windows.

Blender simply pushes that concept to an extreme.

Paolo

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