I think the problem in the OP is that he has a nighttime ritual that involves reading on weekdays, and that ritual is taken away during the weekend. I find these rituals to be very useful in preparing for sleep, so we try to stick to them religiously.

This isn't much of a problem at our house. DD8 reads before bed, but self-regulates pretty well. She'll even ask me to turn out the lights on some nights, where she's ready to skip reading and go right to bed. But we have had some issues with DD not getting enough sleep lately, and we're not making it about the reading time at all. Our focus is on the bedtime. If she's not getting enough sleep, it's time to move bedtime earlier.