I see a lot more complexity here. In the first edit, it sees two links, so it adds 2 archives for each link. In the second, it sees an archive after a different unrelated link and bound those two together. So it added that archive to the beginning. This will start to add new layers of complexity to the bot. Do you suppose it's worth the cost and effort?

In the first diff, it added the same {{webarchive}} twice, even though the source URLs are different.

Medic has been fixing these for a long time, it's able to detect and remove duplicates. They're not as common now because Medic has been cleaning them up but they still occur. Mostly it's because Cyberbot II had a different edit policy and all those will get fixed if Medic continues following behind IABot eventually it will get to them all because IABot adds a duplicate next to the source URL, and Medic detects a duplicate and removes the one at the end of the ref. Sort of a round-robbin.

If we want to retire Medic eventually it should take over because duplicates remain a problem. Editors will add the {{webarchive}} somewhere else in the ref. Maybe an easy solution is just detect for duplicate before adding {{webarchive}}.