I don't know about you, it seems counterproductive to place explanations of why people vote to close in the comments and just seems to incentivise the closing of good, solid questions. When reviewing comments, do you guys think that it is appropriate for comments to explain reasons that they vote to close or not? Or is it justifiable to flag them as being nonconstructive and restricting the core purpose of StackExhange by encouraging the closing and not answering of questions? Thoughts, comments, etc. below.
You're presupposing that the question is "good, solid", but that is not necessarily true (in the context of appropriateness for H.SE).
If a question has issues, commenting on the reason for closure identifies them to the author. That helps the question creator revise it make it more answerable, or otherwise better suited to the SE model. I would think that is the most constructive way to deal with a potentially good question.
Remember, a close vote may be retracted and a closed question can be reopened later. Encouraging the question to be edited into an acceptable format, is much more preferable to the alternative of silently closing a question. The latter simply leaves the author in the dark as to what was wrong.
I fail to see how comments encourages or incentivise closing. If a question has issues, I think someone's probably going to come along and vote to close, regardless of comments.
If I may, I think the argument you are trying to make is that commenting on why you think a question is problematic tends to have the effect of whipping up a mob against it. There actually is a little something to that.
However, a situation where questions get closed with no comment whatsoever is even more problematic, in that the poor poster gets no feedback on where they went wrong. That's likely to lead to them either going off somewhere that's easier to figure out how to participate, or if they are persistent, several annoying rounds of bad questions until they happen to randomly stumble on a way to ask a good one.
If you have a problem with the first effect, I'd encourage posting comment defenses of what look like good questions to you. Since I can't really "vote" for or against closing like a normal user, I've really come to appreciate the power of comments.
Just do us mods a favor and don't get carried away arguing. Make your point as well as you can and leave it. Back and forth discussions belong in chat.