Godfrey
somewhat colored
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Using one camera and lens is certainly valuable as a beginner's step, or as an educational step. Once that step has been taken, going back to it is not really necessary. It would be like putting training wheels on a bicycle again, wouldn't it?
Not really, the analogy isn't very apropos. Doing the one camera-one lens thing is often a quite refreshing different way of thinking about seeing photographically.
You never need to learn how to set a camera properly, just like once you learn to balance a bicycle you don't need to learn that over again. Returning to a single camera and lens is more like refreshing your vision, not re-learning how to use a camera.
G