I get what Tony is saying but I highly agree with cage.  I don't want to see anything so structured that we can't experiment or "accidentally" come up with new ideas.  Sure there are mistakes made, but part of the fun for me is the exploration, whether that is playing in the material room, scripting, building figures and trying new things and so on.  There should be "hand holding" but it should never take away from the discovery aspect.

Instead of a prevention with materials, maybe need more guidelines.  In the manual, which does a great job of explaining things, show an example of each node in use (hell, even include a tutorial folder with each example that could be loaded).  Why not useful tooltips when you mouse over a node?

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