The problems here are you're not saving money by farming materials yourself and crystals actually have a very real value. Just because you have a bunch lying around doesn't mean you can discount what they're worth when figuring out how much crafting is costing you. You could just sell those crystals and have the money instead! And if a given material is worth so much you can't afford to buy it maybe you should farm it up and sell it instead of crafting with it. More to the point, you should have an 'optimal' way to make money and should spend your time doing that in order to buy the expensive stuff instead of farming it yourself.
This assumes, of course, that there is an actual stock of the overpriced item. Right now it seems like a lot of base materials are completely non-existent on the auction house. My goal has been to level woodworking in order to repair fishing rods and make various useful consumables. Every guide says to level in the teens on acid bolts (or some other kind of bolts) because they sell fast and for a reasonable profit. I would love to make acid bolts. But one stack of acid bolt heads has sold in the last 2 weeks. No one is making this stuff. So, if I want to make them myself, I need to level alchemy. Which means I need to level smithing. Hence, reading all the guides, which want me to go kill bees because beehive chips are too expensive on the AH. Gah! Farming is a solution to scarcity and possibly is a good way to make money. It is not a solution to losing money skilling up a craft. If a recipe is unprofitable then it's unprofitable regardless of how you obtain the materials.
BMI: 22.02 (-.07)
Wii Fit Age: 38 (+5)