Worse than that: imagine you have one absolutely damning issue and four weak ones. If the weak ones are swatted away one-by-one or muddled, the reader doesn't even remember the damning one that remains. It even comes off as "well, the person making the accusation prefered to spend time talking about the weak ones while he could have been talking about the ostensibly strong one, so how strong could it really have been?"

I would argue it's nearly always best, both rhetorically and analytically, to reconstruct your opponent's case as generously and sympathetically as possible, and then bear down very hard on your strong point.