As a non-native English speaker, using a thesaurus is often a great help. I do have a pretty decent vocabulary, but sometimes the right word just doesn't come to mind.
Besides using a thesaurus for writing, I occasionally also find it useful for naming things when programming.
the danger with that is always that you end up using words that are subtly inaccurate or that turn your writing into purple prose [0]. For me what really helped as I picked up english (take this with a grain of salt - this was when I was very young and so had the benefit of immersion etc, and i would consider myself fluently bilingual) - what helped me when I learned English was reading a lot of prose by writers that I really respected and that are considered good writers. Particularly contemporary writers, so we don't learn to write like folks from the 1800s. THat helped me learn how words are used in context and pick up the nuances, but it took a few years of course.
As a young adult, I wrote purpley, and I still write that way when I'm excited.
Now, I see information density as a sign of respect and empathy to the reader, and try to optimize in that direction.
It's ironic, because I greatly enjoy novelists like Turgenev, Storm, Mann and Tolstoi: prolific sewers of purple patches. Although Kosinski, Hemingway, and other such literary minimalists are satisfying, too, in their own ways.
Anyways, here are some informal notes that work for me, in effective communication and documentation, if this philosophy interests you:
- allow the reader to stumble over the diction once (needing to look up one word in a dictionary), than to stumble over the grammar two or three times: convert grammatical complexity into diction complexity at any opportunity. In particular, if you can replace a prepositional phrase with a word, do it: many people stumble on prepositional phrases.
- avoid redundant words or repetitions phrases ("I think", "if you think about it", "plan to think about"), unless you're intentionally expressing deference or uncertainty. This unnecessary "stuttering" creates space to read "between", and makes your language more difficult to parse.
- terseness is an underrated virtue. One can almost always shorten a sentence without sacrificing readability. I find arbitrary char limits (per line) and line limits (per paragraph) to be helpful tools.
- "unliterary" or even "poetic" structures – bulleted lists, quotation marks, crazy line breaks, are underrated tools in the terseness crusade.
- for non-printed documents: 1 sentence per paragarph. If your paragraph has 2 or 3 sentences, only 1 is more than 8 words.
- subjects and verbs close together, ideally adjacent. English is Germanic, but it is thankfully not German: no sense in forcing your reader to buffer a subject whilst searching for a verb, or vice versa. Likewise for adjectives and adverbs.
- avoid leading with "it", only to reveal the subject later in the sentence.
- avoid parentheticals. this is hard for me, because I don't tend to think linearly, but if you have something worth sharing, it deserves to be free of parenthetical prison, and easy to read. (exception is if it's a medium-length sentence, at the end of a paragraph, that you want to draw attention to).
- if the reader wants to know more, and your medium is interactive, they will ask. don't overdo it.
The way I typically use a thesaurus, and possibly the way GP is describing, is to use it to remind myself of words whose meaning I know when I see them but aren't coming to the tip of my tongue. I agree that that understanding comes from years of reading.
Besides using a thesaurus for writing, I occasionally also find it useful for naming things when programming.