Jayce, Man of Progress

"If you do" templating is more particular, as seen in cards like Jayce, Man of Progress whose triggered ability begins with, "When you play me, you may kill a friendly gear. If you do, ..." Killing the friendly gear in this case is not a cost for the ability, but a game action that a later instruction checks. If the game action is not performed or is replaced, the later instruction will not have its condition fulfilled - the player didn't "do" it, so "if you do" is not true.