I have what may be a (slightly) different take on the "rules" (which, yeah, I know, are only "guidelines"). Having done a fair bit of writing in my time and having self-studied a little about writing technique, I find it useful to compare what the bonsai artist does in transforming a tree into bonsai with what a writer does in transforming conversation into dialogue.
Dialogue is not conversation. It's "cleaned up" conversation. If you were to try to read a literal transcript of most conversations, you'd find them rather rough going. People do not ordinarily converse with each other in a style that makes for easy reading. They repeat themselves, interject sounds like "um" and "ah", include a lot of relatively useless words (like "you know"), skip readily from one subject to unrelated ones, etc. The writer therefore doesn't write conversation. She takes conversation and cleans it up to get rid of most of these things, and ends up with something that resembles conversation enough to fool us but is devoid of all the confusing and time-wasting elements that would make for bad reading. (Why such things make for good listening but bad reading is an interesting question, but we'll save that for another day.
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Likewise, in bonsai we don't just stick a tree in a pot and let it grow as it would in nature. We clean it up, remove confusing and unnecessary elements, and style it so that it fools the viewer into thinking that it's a real tree while being devoid of confusing and messy elements that might detract from the illusion.
The "rules" are basically just guidelines to help us do that. Sometimes they can be broken to good effect, but usually following them will make for better bonsai, just as following a few "rules" for writing dialogue will usually make for better dialogue.