One more stumbling-block to achievement the ideal in modern interfaces are modes.
A context in which a gesture (a key pressing, a mouse movement or their combination) is interpreted by definitely named by Jef Raskin the mode. Transition to other context (it can be simple start of other applications or keyboard layout switching) is accompanied thus by change of treatment of the same gesture.
By quasi-mode is called thus the mode "held" with a key. CAPS LOCK Key thus creates a mode, and Shift - a quasi-mode.
Jef Raskin was against modes, considering that whenever possible they should will be replaced with quasi-modes. However, all is good within reasonable limits.
Actually an attempt to fit functionality of the big application in quasi-modes conducts to a situation when for a call of any function, fingers on the keyboard should carry out acrobatic sketches.
Application example in which quasi-modes are widely used is Emacs. As opposed to it, the multimode text editor is Vim.
To opponents of modes I want to remind of keyboard layouts. Traditionally keyboard layouts are switched by modes. Attempt to replace with their quasi-modes unlikely will lead to convenience increase.
If to distribute application functionality on modes so that the number of switches of modes will be minimized then modes are more preferable.
However, an obvious problem of modes is that is easy to be forgotten in what mode you be. Under the concept unDE any error which can be easily made, should also easily to be corrected. For example, at a phrase input in incorrect keyboard layout, it is necessary to use gesture of fast double switching of the keyboard layout without text input for correction. In general one of the basic elementary functions of the computer is data converting. And it is very strange that so natural operation as layout correction in any text appears rather not trivial in modern applications.
Also for correction of wrong input of the text in a command mode in the text editor similar Vim it is necessary to have preview area of the entered text (commands) and at fast double switching of a mode the text context in the field will quickly change.
In modern applications quasimodes used for all hotkeys. Even out of a text input mode pressing single keys often at all does not result in any reaction.
In unDE out of a text input mode hotkeys consisting of single keys will be used, but they will not duplicate other functionality which will be used in quasi-modes (for example, work with the exchange buffer). And any errors connected with the mixed mode also will be easy for correction as well as making.