We know that vB tags don’t work in thread titles. What about HTML?
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Hey that looks a bit like a window.
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wibbleelbbiw
Move along, nothing to see
Okay, I now can do “Show single post”. How do I do the linkety-link to a particular post while retaining the thread in which it’s embedded?
I don’t know a direct answer to your question, but I do know that with single posts, like your last two links, the thread title is displayed in the upper right-hand corner. Click on the thread title, and it takes you to the whole thread, conveniently starting with the OP.
Get the post number x from the quote or single-post url and do this:
[post=x]your comment here[/post]
example:
[post=5099238]EddyTeddyFreddy’s post[/post]
Forgot a couple of things.
How to get the post number: hover over the reply or single-quote button and either 1) read it from the url displayed at the bottom of the browser window, or 2) right-click and select “copy shortcut”, then paste the url somewhere and extract the post number.
The “post=” code became available with the version of vB we now have. More info via the vB FAQ link at the bottom of the page.
Hmmmmmm… copying the URL right out of the “copy shortcut” thingie produced a reply page. Let’s try that again:
Right-click copy shortcut from rowrrbazzle’s link to my post
[post=5100432]Okay, try it again[/post]
It works! 
What I did was get the post URL by right-clicking the post number and using copy shortcut, then backspacing out the &postcount=8 part. It was no sweat then to close bracket, open bracket, type post= and copy/paste in the 7-digit post number, sitting right there before me in the URL. Thanks so much. 
Hmmm… one last experiment: Let’s take what I got by clicking and copying the URL from the URL bar itself, to wit:
http: //boards.straightdope.com/sdmb/showthread.php?p=5100432#post5100432
Now, if I were to simply pop in a close bracket after the first appearance of the post number… then add an open bracket, delete the #, and put = between “post” and the repeat of the number, then close bracket… the put [ /post ] before [ /url]…
[post=5100432]Will this work?[/post]
By George, I think I’ve got it!
just ignore me