Reviews don't pile up at the same time. Whereas Alice was already awake when Charlie's question was posted and wrote an excellent review first, Bob took a longer nap, had a coffee, and then noticed that there is another variant that also reviews the question. He begins his post with the following paragraph:
Alice already points out where your Widgets have defects, so let's focus on your Gadgets.
Bob's answer is also excellent. He points out the strengths and weaknesses of Charlie's Gadgets in the rest of his post.
This scenario happens often, although with different levels of quality. Occasionally we end up with answers that start with "as @user said , "continuing from @user" or "@user [...] answer [..] I'll just add the following".
Most of those remarks can be left out without changing the significance of the answer. After all, we're allowed to only look at parts of the code. We don't need to justify that we only covered Gadgets. Unless Bob refers to the content of Alice' answer directly,* it's just additional noise. And while it's unlikely on CR, Alice might delete her answer later and Eve doesn't understand the reference in Bobs answer.
Should we refrain from referring to other answers if we don't actually use any content from those answers?
If the answer is "yes", how should we deal with the situation where one refers to another answer?
- Comment and edit?
* that would need proper attribution and is a whole other beast