Your theory is, indeed, correct. Thanks!
| and I are so similar looking, and I use pipe so rarely, virtually never, in fact, that the difference between the two didn't register; Apple's having used ⇧⌘\ would most certainly have been the intuitive thing to do in this instance.
And I've always wondered why Safari's menu shows ⌘+ for "Zoom In" when ⌘= works just fine...totally unintuitive.
(Hmmm... Now that you've mentioned it, I think I actually raised the | v I issue before; I hope it's burned into my brain this time around.)
