Hi Everybody,
I feel that being able to read music well enough to just sit down and play from the sheet is both a blessing - and a curse.
The reason that I say this is that I can usually tell, just by listening, whether the artist is playing from the dots or not. Most that play from the sheet music tend to play without much expression, as Bill said "is a bit like putting a paper roll in a player piano".
I never have learned to sight read more than single staff music because my first introduction to music was on the piano accordian and I never took piano lessons.
When I started playing the organ in later life, I naturally continued in the same manner - read or memorize the right hand - make up the accompianament. It didn't sound right because until a friend (Grandpa Doug's brother Jim) showed me how to play counter melody with the left hand while beating out the chords, I didn't get that classic "organ sound".
Years later, when I played organ every Sunday for the church, I used the same method to play the hymns and the congregation loved it. They had not heard church music played that way. (I call it "faking", but if it sounds good then people enjoy it). And as Bill said, I never play the same song the same way.
So, the moral of the story is: If you want to be a classical, play by the rules, high technical skill keyboard player, then by all means learn to sight read well.
If you want to be an entertainer, then learn enough reading skills to learn the song and then as you play it, make it sound good. To do this you have to learn to listen to yourself as you play - sometimes when you're busy reading music, you haven't got time to listen to what you are playing.
Like they say, "Pay your money and take your choice!".
Just my thoughts,
Walt