In this case, the rule is just not to use the word "very." I can't think of a single context where "very" doesn't degrade from the semantics and syntax of a sentence. I think this rule is appropriate to any and every style.
Oh, please, then you should broaden your thought process. Sure, "very" is overused/misused. But there are all sorts of places where it is the perfect word, especially when playing like you are talking to a child:
"And when she was bad, she was very, very bad."
Let's all agree that using "malicious" or "malevolent" would "degrade the semantics and syntax" of the sentence.
The number of absolute statements you can make about the English language is very close to the null set.
"Now having a night, a day, and still another night following before me in New Bedford, ere I could embark for my destined port, it became a matter of concernment where I was to eat and sleep meanwhile. It was a very dubious-looking, nay, a very dark and dismal night, bitingly cold and cheerless. I knew no one in the place. With anxious grapnels I had sounded my pocket, and only brought up a few pieces of silver,—So, wherever you go, Ishmael, said I to myself, as I stood in the middle of a dreary street shouldering my bag, and comparing the gloom towards the north with the darkness towards the south—wherever in your wisdom you may conclude to lodge for the night, my dear Ishmael, be sure to inquire the price, and don't be too particular."
Or perhaps more appropriately:
"The truth is rarely pure and never simple. Modern life would be very tedious if it were either, and modern literature a complete impossibility!"
"Very" is a fine word. There's nothing about it that inherently "degrades semantics and syntax." In fact, I think that's probably a meaningless statement. How could it possibly degrade syntax?
It can also be used quite stylishly. Most words can.
That's a much more coherent claim, if subjective. I agree with the weak claim ("it is usually best to drop the very and possibly replace the word it modified"). I disagree with the strong claim ("it is always best ...").
"And when she was bad, she was very, very bad."
Let's all agree that using "malicious" or "malevolent" would "degrade the semantics and syntax" of the sentence.
The number of absolute statements you can make about the English language is very close to the null set.