[aharown07]

Thanks for your patience! I think I get it now... but really this time.

You don't really change the templates, you store your changes and TMS applies them as though you changed the template.
So... TMS doesn't actually "modify templates." That's what was tripping me up... I'm just way, way too literal at times (ADHD? autism? Nah... just a nutcase). Seriously though, who would have thought "Template Modification System" was a "system for avoiding actual modifications to templates"?

I definitely see that avoiding actually changing the templates is the advantage though.
So... since I have a number of templates already edited, what I could do now is put those edits in text files temporarily, revert all the templates and then use TMS to faux-modify them. Then, going forward, vBulletin just sees unmodified templates and upgrades them normally while TMS continues applying my "modifications."

A couple questions though: what happens if...
1. My "insert after" string is not unique... will TMS apply my new code more than once?
2. A future template upgrade by vB removes/alters the string I placed my modification in place of/after/before?