Did that once. Before the Warmog changes. Was a fed Garen just constantly jumping onto the enemy team, doing damage and later on, I'd end up running away with like 1/10th of my HP, waiting for my passive to act up.
Let's say an allied kha'zix ended up saving me for a while, I sat in the bush for 6 seconds and jumped back in with full HP to save KHA from the enemy.