Why is thorn mail not in TT?
Currently hyper carry ADs like Trynd, fiora, and Yi, go bonkers in 3s. They get on a roll and they don't stop, They're exceptionally suited to 3s maps because they need to be peeled (typically done by a 5 man team not just 3), and they're expert duelists, which lends to twisted treeline perfectly. Thornmail is the most direct counter to these types of characters. However, despite the fact hyper ADs perform BETTER in TT, riot decided to remove their only reliable counter.
Why let
,
,
stomp all over the map when there's a perfectly good way to counter them in SR?