It's cool that we can use MathJax to do nice stuff like:

$$\{0+ai,0-ai^\frac{2}3,0+\frac{i}a,0-\frac{i}a\}\forall a \in A \subseteq \Bbb{R}$$  

(stolen from [this Jonathan Allan answer][1])

or this:

$$\sum_{i=0}^n i^2 = \frac{(n^2+n)(2n+1)}{6}$$

(stolen from [this Mathematics Meta answer][2]).

But we also have MathJax being used in cases like [this question][3] or [this question][4] or [this question][5] or [this question][6], where's it's simply rendering digits differently.  Or [this answer][7] where it does indeed help the formatting a bit, but is nothing that couldn't be achieved/communicated with regular characters.


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#Why this might matter

So who cares?  Just use it or don't, as long as the question is clear.  Point taken, imaginary reader, but there might be a few downsides to using MathJax if it's not strictly necessary.


 - Based on [this answer][8], any question with MathJax in the title will be automatically excluded from the Hot Network Questions.  

 - It can, at times, make search results look weird:
[![enter image description here][9]][9]
[![enter image description here][10]][10]

 - Based on [this answer][11], MathJax is likely to eliminate a question/answer from being used on the Tour page.
<sub>Yes that is a very tiny problem.</sub>

 - Also doesn't seem like it works in "tooltips" on question hovering:
[![enter image description here][12]][12]

 - As Alconja pointed out in comments, doesn't work in comments on mobile.

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#So...

 - **Does this matter at all?**
 - **Should we discourage and/or edit out uses of MathJax when they're not really necessary?**
 - **Are there are general guidelines for when it is or isn't worth it to use MathJax?** E.g., $x^2$ seems obviously better than x^2, but is $4-3=1$ that much better than 4 - 3 = 1?


  [1]: http://puzzling.stackexchange.com/a/36023/21234
  [2]: https://math.meta.stackexchange.com/questions/5020/mathjax-basic-tutorial-and-quick-reference
  [3]: http://puzzling.stackexchange.com/questions/11161/two-students-guessing-positive-integer
  [4]: http://puzzling.stackexchange.com/questions/44635/sequence-seen-on-the-street
  [5]: http://puzzling.stackexchange.com/q/42887/21234
  [6]: http://puzzling.stackexchange.com/questions/25979/complete-the-numerical-sequence
  [7]: http://puzzling.stackexchange.com/a/43290/21234
  [8]: https://puzzling.meta.stackexchange.com/a/2847/21234
  [9]: https://i.sstatic.net/3Easp.png
  [10]: https://i.sstatic.net/OYlhJ.png
  [11]: https://meta.stackexchange.com/questions/163947/what-determines-the-questions-available-for-selection-in-the-about-page/163948#163948
  [12]: https://i.sstatic.net/o6gC7.png