What is the difference between a masterwork schematic and a normal one?

I found two different schematics, the "Masterwork Witch Staff" and "Superb Staff of the Dragon" both have the same dps range (71/94). Both also have a masterwork slot. What is the difference between them? Is a masterwork schematic guaranteed to give me a masterwork weapon and so is better because I don't have to waste the masterwork slot with one of the "Increased chance of masterwork" items? If so, is it ever worth it crafting a non-masterwork weapon?

Unfortunately the word masterwork is overused in DA:I's enchanting system:

• The schematic can be a masterwork schematic. In this case, the schematic accepts a greater number of materials compared to other schematics of the same tier. Compare the witch staff schematic with the masterwork witch staff schematic: the former has a 16/6/6 arrangement of material slots where as the later has a 18/7/6 arrangement.
• During crafting you can add something to the masterwork slot. Once you get an arcanist to help you, you will be able to add Fade-touched materials while crafting armors and weapons. These will give the created item a unique property like casting a spell on weapon hit or healing a percentage of received damage.
• Finally, it is possible to craft a masterwork item with a critical crafting success. This is done by adding an item like ironbark or great bear claws into the masterwork slot and then passing the RNG check. If the critical crafting is successful, the item generated will have 10% better stats.