1. Some people consider running heroics with guildies to be fun and not as a torturous means to a Chaos Orb, so they price Orbs as a byproduct of non-work (ie: very low).

2. TSM isn't all-knowing, no. It won't tell you "yes, Bronze Shortsword is listed for 900g and costs 5g to make... but nobody's gonna buy that." But nothing really can. Even The Undermine Journal will only get you so far.

It's about picking your battles. You go through in TSM and decide "I think THESE items will sell" and you disable the rest from your auto-queue. Then you go out and make one or two of those items, post them at your chosen prices and see what happens. If nobody buys them after a while, take the loss and remove the items from your auto-queue.

It's also common sense. If TSM recommends that I get 7 types of mats together to craft a level 31 cloth turd vest of +agility/+spirit/+holy resist, I'm gonna disagree with it.

Hardened Obsidium and Stormforged won't sell on your server? Dial it back further. Some Wrath, BC and Vanilla crafts DO sell, because they're still really useful when leveling. Blacksmiths have it best since they can cover the leather->mail/mail->plate transition at 40 and can also craft each of the tanking sets that appear throughout the levels (the Adamantite Set for level 65-67 sells decently).

3. Look up leveling guides for professions you want to make gold with. Now remove every item you see on that list from your TSM auto-queue. Those lists are the most cost-effective ways to level a profession, so even if people don't look those up, what's on them is pretty obvious and so every crafter's going to make 10 of those and post them for "at least I'm not vendoring it" prices.