Whilst I agree with most of what is being said here, I do think that if we all stuck rigidly to the music, it would become very boring. To change or 'tweak' chords etc., makes the music more interesting and colourful. I also think changing styles to certain types of music, adds to the interest. As an example, I have been playing 3 Blind mice to a boogie rhythm since I was 8 years old (and no! I'm not going to tell you how many moons ago that is) To this day, it still surprises people when I play it to a boogie rhythm. As Bernie said, for some of us the given chords are just a guideline.

Having said all that, for me,there is nothing more pleasurable than hearing a good piano played by a first class pianist, whatever type of music is being played.

Audrey