"Here's another possibility I hadn't mentioned previously. Maybe even damage below the irreparable state causes severe trouble, like the time/space chaos we've observed in the later books. Things like rooms changing places or the Village in Shiota or Hinderstap."

I said something similar to this ine one of my replies. My argument went like this: There was a lot of damage to the Pattern done during the War of Power, this damage was lessened when balefire stopped being used en masse but it was not halted because the Dark One continued to touch the world. In the current Age, the Pattern may not have fully recovered from this past damage, especially given that the world is still reeling from the W.O.P. and The Breaking, so using balefire in such a way at all may be enough to cause a serious rupture in the Pattern.

I think the best way to envision the Age Lace would be to think of the Narrative Chart AesJedai posted in a separate thread (link is attached). Though the flow of the chart does not show specific character actions, you can chart each character's whereabouts during climactic parts of the War of the Ring. Given a sufficient familiarity with the Book, you can say that removing certain threads causes the entire tapestry of lines to fall apart, because during particular moments, the lives and wellbeings of others depended on the actions of that particular thread. Using WoT terminology, for example, if you balefired Arwen, who in the grand scheme of things had a relatively small part to play in the movie, from time/space before she rescued Frodo, Frodo would be dead, and the entire tapestry would fall into a new form after many fluctuations - the yellow-bordered green line may or may not survive the poisoned wound, or it may not make it to the Ring's Destruction. Given that we don't know the relative importance of each and every thread in the Pattern, nor what these threads were supposed to do in the future, you could cause a major rupture in the Pattern by the removal of many such "one note" players.