I agree with you, ethbro, it is a valuable life lesson. I can personally attribute most of my social successes to the ability to gauge the interlocutor and their interests, and such a skill will gain one a rep as a good listener.
You're welcome, Doug. I also enjoyed checking out your personal site in your HN profile - that crazy interface seems tailor made for a Mobile user to "explore"! Lots of fun.
If I am reading correctly, if person S sends person R a message M bearing hash tag H, if R sends their own message M2 to S bearing hash tag H2, then M will be revealed to R and M2 will be revealed to S, if and only if H equals H2. (S may choose some behaviors, such as revealing their identity, in order to prompt R into sending a message.)
As for your second paragraph:
I like this site's design<1> a lot. I was able to skim it quickly, and absorb enough to answer your question and more. With respect, I think more work has gone into its design than "antiquated" would suggest.
For one example, on mobile the body paragraphs on the right of the screen can themselves be dragged to the left to read all the info, instead of my having to use the tiny fiddly scrollbar. I think that's a smart feature for a mobile site with a fair bit of text (such as on the SQL page.) Consider also that the site uses colors for text, background, and UI elements (body, nav, etc) that neither clash hideously nor strain the eyes with too-low contrast; plenty of old websites don't take that level of care (think a typical professor's academic homepage - now THOSE can get antiquated!)
Bootstrap will get you a "modern"-style site without too much effort, but I don't think it would add anything here.
<1> By design I am waving in the general direction of layout, color scheme, ease of use, etc.
I'm curious: within which field are you doing this PhD? I could see you as a computer scientist, systems designer, political theorist, perhaps an economist or philosopher.
[not the person you responded to]