Okay, I'm going to bet that everyone here has at some time in their life fried bacon, or seen it fried, or cooked some other meat. How hot did it have to be to start melting the fat? And how much does it burn if you splatter a bit of that melted fat on yourself? Everyone have the picture now? Good. How much heat would this device need to apply to melt your fat? And what would that do to the rest of your body if you had that hot, melted fat trapped inside? *shudders* Yes, obtaining severe burns will melt away fat, but that hardly seems like a good approach.
The reality is it's the same old gimmick...you'll lose some water weight from sweating, but as soon as you rehydrate, you'll put it all back on.