It’s really just one more layer to the gear grind. If you’re into such things, the Forge makes it a little more interesting. If you’re the kind of person who does the math, I think you’re probably missing the point. The point of the game, from my perspective, is to experience interesting things in interesting ways, not to bean-count.
With that said, I also don’t see the point, but then again, I don’t really care about trying to get this gear or that nor concern myself much with game economics. I’m more interested in seeing the world. The gear grind really just detracts from that.