Based on the discussions below, it seems clear to me that there are (at least) two continuous dimensions of legibility and coercion, which are often related but conceptually distinct. I think they are positively correlated in most good writing, so they are easily conflated, but clarifying them seems useful.
The first is Legible <--> Illegible, in Venkatesh Rao’s terms, as others suggested. This is typically the same as serial-access vs random-access, but has more to do with structure; trees are highly legible, but may not require a particular order. Rough notes from a lecture are illegible (even if they are typed, rather than hand-written,) but usually need to be read in order.
Coercive <--> Non-coercive, mostly in the negative sense people disliked. Most of the time, the level of coercion is fairly low even in what we think of as coercive writing. For example, any writing that pushes a conclusion is attempting to change your mind, hence it is coercive. Structures that review or present evidence are non-coercive.
I think it takes effort to make something legible but non-coercive, and it is either very high effort OR badly structured when they are illegible and non-coercive. And since I’ve brought up Venkatesh Rao and mentioned two dimensions, I believe I’m morally required to construct a 2x2. I can’t upload a drawing in a comment, but I will “take two spectra (or watersheds) relevant to a complex issue, simplify each down to a black/white dichotomy, and label the four quadrants you produce.” Given his advice, I’ll use a “glossary of example “types” to illustrate diversity and differentiation within the soup of ambiguity.”
Paternalistic non-fiction writing is legible but coercive; it assumes it knows best, but allows navigation. The sequences are a good example, well structured textbooks are often a better example. Note that being correct doesn’t change the level of coercion! There are plenty of coercive anti-evolution/religious biology “textbooks,” but the ones that are teaching actual science are no less coercive.
Unstructured Wikis are illegible and non-coercive; the structure isn’t intended to make a point or convince you, but they are also unstructured and makes no effort to present things logically or clearly on a higher level. (Individual articles can be more or less structured or coercive, but the wiki format is not.)
Blueprints, and Diagrams, are legible but non-coercive, since by their structure they only present information, rather than leading to a conclusion. Novels and other fiction are (usually) legible, but are often non-coercive. Sometimes there is an element of coercion, as in fables, Lord of the Flies, HP:MoR, and everything CS Lewis ever wrote—but the main goal is (or should be) to be immersive or entertaining rather than coercive or instructive.
Conversations, and almost any multi-person Forum (including most lesswrong writing) are coercive and illegible. Tl;drs are usually somewhat illegible as well. The structure of conversation is hard to understand, there are posts and comments that are relevant that aren’t clearly structured. At the same time, everyone is trying to push their reasoning.
While legibility is about readability as a result of how something is written/appears, readability is also affected by length. If a chart is bigger and more complicated it can convey more nuance—at the cost of being harder to read, and taking longer. While font can usually be changed without disrupting the message, it’s more work to do this for length, if it can be done at all without trading off in way that aren’t improvements. (If I invented a language for conveying messages more succinctly in visual form, and this message as a whole was 13876, that wouldn’t decrease the amount of time it takes to read (and understand it) it.)
Based on the discussions below, it seems clear to me that there are (at least) two continuous dimensions of legibility and coercion, which are often related but conceptually distinct. I think they are positively correlated in most good writing, so they are easily conflated, but clarifying them seems useful.
The first is Legible <--> Illegible, in Venkatesh Rao’s terms, as others suggested. This is typically the same as serial-access vs random-access, but has more to do with structure; trees are highly legible, but may not require a particular order. Rough notes from a lecture are illegible (even if they are typed, rather than hand-written,) but usually need to be read in order.
Coercive <--> Non-coercive, mostly in the negative sense people disliked. Most of the time, the level of coercion is fairly low even in what we think of as coercive writing. For example, any writing that pushes a conclusion is attempting to change your mind, hence it is coercive. Structures that review or present evidence are non-coercive.
I think it takes effort to make something legible but non-coercive, and it is either very high effort OR badly structured when they are illegible and non-coercive. And since I’ve brought up Venkatesh Rao and mentioned two dimensions, I believe I’m morally required to construct a 2x2. I can’t upload a drawing in a comment, but I will “take two spectra (or watersheds) relevant to a complex issue, simplify each down to a black/white dichotomy, and label the four quadrants you produce.” Given his advice, I’ll use a “glossary of example “types” to illustrate diversity and differentiation within the soup of ambiguity.”
Paternalistic non-fiction writing is legible but coercive; it assumes it knows best, but allows navigation. The sequences are a good example, well structured textbooks are often a better example. Note that being correct doesn’t change the level of coercion! There are plenty of coercive anti-evolution/religious biology “textbooks,” but the ones that are teaching actual science are no less coercive.
Unstructured Wikis are illegible and non-coercive; the structure isn’t intended to make a point or convince you, but they are also unstructured and makes no effort to present things logically or clearly on a higher level. (Individual articles can be more or less structured or coercive, but the wiki format is not.)
Blueprints, and Diagrams, are legible but non-coercive, since by their structure they only present information, rather than leading to a conclusion. Novels and other fiction are (usually) legible, but are often non-coercive. Sometimes there is an element of coercion, as in fables, Lord of the Flies, HP:MoR, and everything CS Lewis ever wrote—but the main goal is (or should be) to be immersive or entertaining rather than coercive or instructive.
Conversations, and almost any multi-person Forum (including most lesswrong writing) are coercive and illegible. Tl;drs are usually somewhat illegible as well. The structure of conversation is hard to understand, there are posts and comments that are relevant that aren’t clearly structured. At the same time, everyone is trying to push their reasoning.
While legibility is about readability as a result of how something is written/appears, readability is also affected by length. If a chart is bigger and more complicated it can convey more nuance—at the cost of being harder to read, and taking longer. While font can usually be changed without disrupting the message, it’s more work to do this for length, if it can be done at all without trading off in way that aren’t improvements. (If I invented a language for conveying messages more succinctly in visual form, and this message as a whole was 13876, that wouldn’t decrease the amount of time it takes to read (and understand it) it.)