Here's the definitive answer to "Why vi?". Came across it on my hard 
disk, saved it once from a Unix group IIRC.

         MORE AND MORE PEOPLE CHOOSE `VI'. CASE OF STUDY
 
   This article is just a part of a fundamental opus devoted to investi-
gation  of  UNIX. Scientists of the future will read UNIX's manual pages
with the same feel of a light perplexity that comes to us when  we  turn
the  pages  of `Witch Hammer' (some people feel it right now). This work
should help them in their heavy task.
   Let us consider a very obscure question - why people  like  `vi'  and
why it looks like `vi'. Certainly, there must be lots of convincing rea-
sons in deleting a character by pressing three keys `ESC', `x', `i'  in-
stead  of single `del'. We should immediately reject opinions like `peo-
ple search for obstacles to overwhelm them' as unscientific ones.   Con-
sidering this issue more thoroughly we can find at least four approaches
to it.
 
   (o)  Astronomical point of view. As we know most of programmers  work
        putting  their  legs on the system block. (If you have a `tower'
        just move it from your table  to  the  floor,  you'll  feel  the
        difference!). To achieve maximal comfort legs should be arranged
        along the magnetic lines. Well, let us take a look on  the  key-
        board  laying over your mmmm... stomach. In this position a line
        connecting keys `x' and `ESC' points right to the North star. At
        the same time `x' - `i' axis indicates the equinoctial point.
 
   (o)  Magical approach. After active usage of described  above  `ESC',
        `x',  `i'  key  sequence  everybody comes to the conclusion that
        SOMETHING'S WRONG and enters another sequence - `ESC', `:', `q',
        `!'.  As  we know `ESC' abbreviates the word `escutcheon'. If we
        consider keys `x', `i', `:', `q' and `!' we can notice that they
        organize  a  magic  pentagram. It is clear that multiple drawing
        the pentagram protects us from the cruel daemons hidding in  the
        CPU.
 
   (o)  Medical reasons. Clinical researches show that using `vi'  keeps
        tonus of your fingers at the level of a violonist, that prevents
        a gout. However, you should be careful working at home. Be shure
        that  the  door  to the chield room is tightly closed unless you
        want to hear from your son the sentences you usually address  to
        `vi'.
 
   (o)  Psycho-analysis. Sexual instinct...
 
                           ******
                   (for specialists only)
 
   In conclusion I would like to state that we are currently at the very
beginning  of understanding deep laws ruling over the world. Some impor-
tant questions remain unexplored. For example, why are we  using  `ESC',
`d',  `d',  `i' to delete a line rather than handy `ESC', `f', `d', `h',
`s', `t', `h', `n', `v', `b', `i'?
   Never mind, `vi' should overcome some day!