For this reason, I tend to err on the side of conservativeness when translating. For example, I still capitalize "Internet," even though fewer and fewer people do so, and in a few years most people probably won't. I prefer to stay a little behind the times, because I don't want the writing style to stand out so much that the reader starts to notice me, the translator, instead of the document's content.

Nevertheless, my clients tend to be more conservative than me. Part of this is because almost all of them are Japanese, so in addition to lacking a firm grasp of English and all its subtleties, they're heavily influenced by what they learned in school textbooks, which tend to be several decades out of date from current usage.

As a result, I often find myself trying to persuade my clients (usually in vain) to be less conservative and formal with their English. When a client asks me to revise a translation so it's more formal, I give them my arguments for why the tone of my writing is correct, including references from technical-writing style guides. For example, the Microsoft Manual of Style for Technical Publications has this to say about formality in writing:

Most of the writing that we do for our customers can be considered formal writing. Formal, in this context, does not mean stiff or academic or overly passive. It simply means that we convey a professional image of competence and helpfulness. There is no contradiction between formal writing and a friendly tone.

I do note here that MSTP doesn't like to use contractions. In this sense it's even more formal than my other style bible, Read Me First! by Sun, which says that contractions are fine as long as they don't cause confusion for translators (!).

Both books make the point that a more conversational tone actually aids understanding. People reading technical documents are there for information, not for a pleasant read by the fireside. Using lots of jargon and highfalutin grammar just slows them down. My own views on this are influenced by the Head First series by O'Reilly, which consciously uses a very informal style that's based on solid research about how people acquire and retain knowledge.

And this brings up another problem: views of proper levels of formality for technical writing differ in the Japanese and English-speaking worlds. Even though there's a lot of difference even between English-speaking countries as to how formal writing should be, I think there's a general agreement that technical writing should be friendly, without being presumptuous or smarmy. Meanwhile, what I hear a lot from Japanese clients is that they want the writing to be 丁寧 (teinei), which can be translated variously as "polite," "considerate," "painstaking," and "scrupulous." It's very hard to convey that this kind of approach doesn't work as well in English, because people tend to think that their unexamined core values, like what constitutes politeness, are universal.

Some clients get it; I'm sure that we can all point to Japanese high-tech companies that have great English documentation. But it's also true that most of them have stilted, hyper-formal English, and while this is partly because a lot of Japanese-to-English translators are out of touch with real-live English technical writing, the dirty little secret of the technical English world in Japan is that much of the English is horrible because the companies prefer it that way.