The thing of it is, you may have come to terms with the idea of robotically following a routine without understanding why you're doing it and why it works. But it should not mean you are to subject your students to the same misfortune. I know it's a harsh reality when you find out what you thought you know isn't exactly right. It's like finding out the guy you thought was totally into you is actually madly in love with someone else. If you continue on as if you and him have a future together you'd be living in a false reality.
Now let's apply that analogy to math instruction. You've found out that the math instruction you've been using for the past 5, 10, or 15 years is not as effective as you thought it was. So are you going to continue on in the same manner even though you know the truth? Or do you push pass the discomfort of not knowing and begin to develop your own understanding in order to meet the needs of your students?
The Cookie Monster song: http://youtu.be/Ye8mB6VsUHw