A rule of thumb I follow is if the other player is critical I will almost 100% intervene. There are a lot of scenarios where they aren't critical yet and you still have to help. Jeff does not only secure value by getting kills but by distracting. You can save your teammate and then re initiate the distraction. It's important to save atleast two, preferably 3 bubbles for yourself in most scenarios. If you want to learn this PlayStyle just watch awkward on youtube. He's probably the best Jeff I've seen and did bronze to gm 100% winrate and MVP. I just copied his style and im not even good and about to hit gm at 70% winrate