I believe that equal opportunity is just that - equal OPPORTUNITY, not equal treatment. In other words, leveling the playing field.
I have four children. Each is amazingly unique. Each has talents and weaknesses. I learned very quickly that what worked with one child discipline-wise (or as encouragement) didn't necessarily work with another child. So the point was that I disciplined and encouraged FAIRLY - not THE SAME.
One child responds to and needs lots of quality time. Another - little gifts or notes. Another - public praise. One child needed, quite frankly, to be spanked on occasion - or just the THREAT of a spanking. Her sister? I could have beat her into the ground and it wouldn't have made a bit of difference - but time out standing in the corner worked wonders. My youngest son responded best to having to write out what he had done wrong and how he could have handled it better.
The point, the challenge, and the requirement of effective parenting though, is consistent and fair discipline and encouragement - and the best method differs depending on each individual child.