I’m not sure where this idea comes from exactly, but some people seem to feel that writing in a vague, overly-complicated style is more professional than writing in a simple and direct style. I can only suppose this idea comes from a literary background, hearkening back to bored students dozing in their 18th century literature classes.
I once had a friend ask me to write her a strong cover letter for her CV. Her cover letter was a mess of passive voice, $5 words, and six-line sentences that were so riddled with commas, I was surprised the letter wasn’t dripping with fresh blood.
I cleaned the cover letter up, using strong verbs, shorter sentences, and the active voice. When I handed it back to her, she rejected all my changes saying that the simplicity and clarity of the letter made her look unsophisticated.
When it comes to technical documentation, writing in a clear, direct, and active style should always be the goal. You may find it necessary to write vaguely or passively, but you need to evaluate each case carefully.
Writing in this direct style not only makes it easier to know who is doing what, it can sometimes expose weaknesses in the product you are writing about. If the specifications are written in a passive, vague manner, this often means the writer was unsure of his material, so he tried to gloss it over with vague phrasing, hoping the reader doesn’t ask too many questions.
But when you attempt to rewrite it in a clear, direct manner, you realize that you may need to guess who is doing what to who, and how, and when, and even why. The specs aren’t providing any of that key information; the vagueness of the document implies that you know all of this already (with an unhealthy undercurrent of suggesting you may be dolt for not knowing).
It is in this rewrite in the active style that you can really shine in doing your job. Go find out the answers to these mysterious questions, and not only will your document be stronger, maybe the product you’re writing about will be improved as well.