The only numbers I will ever spell are one and zero, and only when using them as a pronoun, or for emphasis, respectively.
Is there ever a reason to not to use symbols when dealing with numbers? Why would "fourteen whatevers" ever be preferable to "14 whatevers". It's just so much easier to read numbers as symbols, not spelled out.
(Caveat, not including multipliers, like "273 billion").
The real style guide is always your reader. If specific numbers may be searched for or copied, it is kinder to use symbols. If your reader is merely reading a number in conversation, it would usually be better to follow the usual style guide.
The more you know and care for your reader, the better your writing will be.
Me writing zero point zero zero zero zero zero zero zero zero zero zero zero zero zero zero eight five six two one three four nine two to improve the readability of the document by writing numbers less then ten as words.
Not only did you write those numbers wrong but none of them are less than 10. Maybe the readers perceived ambiguity has less to do with their standard conventions than you think.
You're in an engineering community, is ten-one actually wrong?
Consider the sequence: One, eleven, twenty-one, thirty-one, fourty-one, fifty-one... One hundred and one.
As far as the convention of writing numbers out in words when they're less than 10, there's also conventions for less than 15, wikimedia uses the convention if it can be written in two words it's optional to write it out as words.
Just a small note on this, style guides have all sorts of weird rules about spelling out numbers, most of which I personally think are nonsense, hence making a meme. Not necessarily just less than 10