**Re the Deletion, [because @gparyani has sent PMs to those of us who voted to close asking for explanations][1]:**

For the reasons detailed in comments and others this question should be deleted, but additionally:
 - **It will not be answered to OPs satisfaction**, though the correct answer has already been given by several, and first by the very first comment made on that question.
 - **Its continued existence on the site is just clutter** and may dissuade future visitors who have more specific and clear (probably mostly simpler, but I don't pretend to know what every possible question about case airflow could be or whether it can be presented in a way so as to be on topic here).

I do not see value in the question remaining, and light of SU's overall goal of attempting to be a compendium of good questions and good answers, this question which cannot be answered well (taking a broad definition of "well" here, see above) should be deleted.

**Editing to add:**

When questions are closed, sometimes the reason noted at the top is just one of several possible reasons. It is pretty common for a question to fail on several points, and I think this one does.

Please note that I will refer specifically to points in the question OP has memorialized in their [own screenshot][2].

 1. **Wanting an "objective explanation" doesn't mean there is one**, and a point that has been made in this discussion, ad nauseum, is that sometimes complexity has an irrevocable connection to there not being that sought for or expected objectivity. This specific situation approaches extreme levels of complexity if you dig deeply enough to find that "*objective* explanation". This is, perhaps, the weakest argument, in my opinion, because there IS, at some depth, a firm answer, and sometimes it surprises me the way clarity and simplicity is arrived at and communicated by one or another member on this site.

 2. **The post asks multiple questions**. This is clear on its face. The Title contains two questions, the body contains a few more as asides and tangents. "Will I benefit from...", "how should I configure them?", "would adding airflow from the top fans...", and what I think is probably the core problem here "...I don't know how the various concerns should be weighed against one another...". This is also a relatively weak reason, but a reason nonetheless.

 3. **The question is admittedly theoretical** and not practical. OP dismisses the question of whether they NEED more cooling as opinion based, but it isn't actually. *Whether a computer does or does not need more cooling can be known simply and by fact*. OP asks the community to ignore that aspect, (see "regardless of whether I "need" more cooling"), and then asks us to focus on "principles". 

 4. **The title's first question is a weak question** and solicits opinion: "Will I benefit from..." Maybe? Probably yes, but why? This sort of question comes up pretty regularly here on SU. "How..." and "What..." questions are more likely to have the concreteness that SU expects, while "Does..." and "Will..." and "Can I..." are often correctly and completely answered by "yes", "no", or "maybe" answers, and most people who ask those questions then find some frustration as they learn the question that was in their mind is NOT what they communicated in typing it out. Sometimes, these sorts of questions get that probing "why" in the comments, and DrMoishe Pippik served that question ably in the first comment, which gets to the heart of the problem here.

 5. **The correct course is to challenge OPs assumptions** so that they can get to the real issue, or accept the clearest truth. While OP wanted us to ignore whether or not their computer needed more cooling, the question of how to cool a computer is directly linked to whether their computer is sufficiently cooled or not. The very first comment, given just an hour and a minute after the question is posted, gives this challenge: "If your PC is not overheating, why do you need another fan?". In their reply OP doubled down on the theoretical nature of this question, reiterating they want answers that "...will help me understand how to make similar choices in (the) future". OP had 5 years to improve their question, focus on practical issues, etc. At this point this question is very likely moot as it is VERY likely that OP's computer hardware has changed and so the root details of the question have as well.

While this site only shows one specific close reason, there are ample reasons for this question to have been closed, and for it still to remain closed.

  [1]: https://meta.superuser.com/questions/15160/i-genuinely-dont-understand-why-this-question-was-deleted-when-i-asked-for-it-t?noredirect=1#comment44973_15160
  [2]: https://i.sstatic.net/uAxgw.jpg