[Bruce Tognazzini, "Tog on Interface", Addison-Wesley pp
26-27]

We've done a cool $50 million of R&D on the Apple Human
Interface.  We discovered, among other things, two pertinent
facts:
* Test subjects consistently report that keyboarding is faster than mousing.
* The stopwatch consistently proves mousing is faster than keyboarding.

This contradiction between user-experience and reality
apparently forms the basis for many user/developers' belief
that the keyboard is faster.

People new to the mouse find the process of reaching for
it every time they want to do anything other than type to
be incredibly time-wasting.  And therein lies the very
advantage of the mouse: It is boring to find it because the
two-second search does not require high-level cognitive
engagement.

It takes two seconds to decide upon which special-function
key to press.  Deciding among abstract symbols is a
high-level cognitive function.  Not only is this decision
not boring, the user actually experiences amnesia!  _Real_
amnesia! The time-slice spent making the decision simply
ceases to exist.

While the keyboard users in this case feel as though they
have gained two seconds over the mouse users, the oppositie
is really the case.  Because while the keyboard users have
been engaged in a process so fascinating that they have
experienced amnesia, the mouse users have been so disengaged
that they have been able to continue thinking about the
task they are trying to accomplish.  They have not had to
set their task aside to think about or remember abstract
symbols.

Hence, users achieve a singifcant productivity increase with
the mouse in spite of their subjective experience.

Not that any of the above True Facts will stop the religious
wars. And, in fact, I find myself on the opposite side in at
least one instance, namely editing.  By using Command-X, -C
and -V, the user can select with one hand and act with the
other.  Two-handed input. Two-handed input results in solid
productivity gains (Buxton, 1986)

[Buxton, William (1986).  "There's More to Interaction than
Meets the Eye: Some Issues in Manual Input," in D. Norman
and F.W. Draper (Eds.), New Perspectives on Human-Computer
Interaction, Lawrene Erlbaum Associates, Hillsdale, N.J.]


