Why typing in Word specifically?  I'm typing this e-mail and that's just as much writing as if I were writing in Word.  I use key echo when writing because it informs me of errors that I can correct as they are made.  This isn't necessary, I check messages before I send them but I want to know if I make an error when I make it and correct it then.  Using letter echo doesn't always tell me when an error is made for one reason or another but it helps.

If someone uses a synthesizer that is not responsive and the echo is too far behind the key press, using character echo becomes an impediment.  If I use Via Voice or Eloquence, the response is immediate.

Gene