It seems to me, most power transistors with a metal tab have the tab connected to the collector. What I don't understand is how the transistor is intended to be used. For example, I want to break the ground connection to an inductive load with the load connected to the collector and the emitter connected to ground. Nothing new, see it done everywhere, and it works, but I have to insulate either my heatsink from ground, or the transistor from the heatsink. It seems it would be so much simpler if the tab were the emitter and I could bolt it directly to a large structural ground/heatsink, but from what I can see transistors are not made that way. Why not, and what am I missing about the use and connection of transistors and heat sinks? I know this is really a beginner question, which I am, but I have a real mental block about this so please educate me. Thank you