Between the levels of 40-50 Machinist doesn't get a single skill

[Fannah]

Why would you need to control your heat before level 64? (64 is the level when you get the main bonus for being from 50 to 95).
You will gain 10% for 10sec once overheating and that's all. You will then lose those 5% from Gauss Barell for 10sec. I don't see the problem. Heat management has no real purpose until 62 (when you are able to use your heat to use Cooldown, which is like a free Slug Shot, and a full ability to spam it during overheat).