Yes, in writing the answer I was thinking this out to be an aTbRef article (if not in the manual too). As regards aTbRef, it won't be for a couple of weeks though as I'm busy tinkering with that doc so won't be adding any
new pages in the interim.
I should add that I wish I was as diligent in applying the above techniques as my comments might make it appear. The irony is that it's so easy to dive into quite complex things in TB that one also all too easily moves quickly past the point of realising "Ah, I ought to make some modular tests, before using my live data.". However, the worst penance for that error is usually only frustration. Most care needs to be taken when synching with other systems or using complex cascading actions. The latter, especially
are worth testing on a deliberate testbed and/or a copy of real data before using your real live data. As with much in life you generally find the correct point for shifting to a deliberate test by getting it wrong … (at least) once.

Saving notes like above? Open your reference TBX, add a note and open it's text window. Now open the URL such as
http://www.eastgate.com/Tinderbox/forum//YaBB.pl?num=1321833832/1#1(my notes upthread) in a web browser and drag the URL into the taxt pane. $URL is set and displayed as a key attribute. Or just drag the URL into your main view (outline, map, etc.) and a new note is made for you with $URL set. Or just use Yojimbo, DevonThink, etc. to store the URL.
Incidentally, from experimentation, the thread URL syntax is like this:
.....YaBB.pl?num=1321833832/1#1The red is the UD for the thread. Leave off the rest of the above after the ID and the thread opens at the opeing post. Want to open the thread scrolled to answer #4? Just add the blue bit above, in this example '
/4#4' after the UID. BTW, no idea why the post number's repeated, i.e. why it's /4#4 not /#4.