This is just personal opinion, but . . . I would have rejected that edit.
The edit absolutely changed the author's meaning. Heck, the anonymous user who suggested the edit began the third paragraph with
I guess my theory
Emphasis on the "my". The user who suggested the edit was modifying it with their own ideas.
Now, Mourdos added a note about the decision, saying
I approved this edit (/pending edit) on the assumption that the annon user was SRG. SRG, if you log in to edit your answer, we don't have to manually approve it.
I wouldn't assume one way or the other in this case (although leaving a comment was the best thing to do). I've seen loads of edits where a user tried to add on "helpful" information, but was someone completely different. I would think this could be the case.
Did the edit help? Yes. But I would either have rejected the edit or skipped the review (though I probably would have rejected it). If the author wants to add that information in, s/he can do it him/herself at a future time. A modified version of Mourdos' comment could have worked:
I rejected this edit (/pending edit) in case the anonymous user was not SRG. SRG, if you log in to edit your answer, we don't have to manually approve it. You can then edit your post as you wish.
Better to be safe than sorry.