Lighting is extremely important, it is just that you might not need as much intensity or duration as you might of been led to believe.
It also appears that the colour spectrum is not as important as some might have you believe, however for my own eyes, I like to mix a couple of colours to get a nice pleasing effect from the tank.
I also like to change the colours when I re scape the tank, just to please my eyes, like re decorating a room!
At the moment I have a 6500 k & a 8800 k but I must of used dozens of different configurations over the years...