The Webu Sayadaw emphasized the importance of picking a single practice and sticking to it, and he never said that that practice has to be anapana sati.
To Light a Fire:
> You know about many different techniques, but you don't have to practice them all. Choose one and work with it. If you keep your mind steadfastly focused on one object, you will immediately be aware of what you have not been aware of before, just as you see light as soon as you turn on the switch. Can there still be wrong view and delusion in your mind while you are thus aware?
> Every technique the Buddha taught will work as a switch to turn on the light.
Regarding continuous practice, it's commonly said that the Buddha recommended practicing "in all four postures": sitting, standing, walking, and lying down.