My notes on five-mask runs:
* With a rank 15 cloak, you do not need to pull quickly or do big pulls. I never pull more than one trash pack at a time outside of the starting zone, and never pull a trash pack with an elite. Avoiding mishaps and understanding your mistakes is more important than going fast.
* High-mask runs are generally easier solo or in a group of two. You have more control over mob positions and burned bridges is less of a factor. If you do go in a full group, have someone go tank and let that person pull.
* Trash packs do not drain sanity, except by making you run over burned bridges. Their abilities go after your health, and at five masks they can kill you pretty readily. Identify casters (especially ones with names like Tormentor or Dominator) and kill them first. If there are multiple casters, line of sight can often be used to group them up. You can use purification protocol to stun aberrations, particularly tentacles that will otherwise waste your time by burrowing.
* Elites are trying to drain your sanity. Every elite has two abilities, one of which is sometimes more subtle than the other. Pay attention as you fight them; if you have unexplained sanity loss, look them up on wowhead after the run. For example, the elite before the valley of spirits (Orgrimmar west) has a decimator ability that sends a projectile out and then back. If you only dodge his charge and not his decimator, you'll lose a ton of sanity with Daredevil active.
* Picking up sanity potions is a pretty big boost. Doing some lower-mask runs where you try to get all of the chests and odd crystals will help you get familiar with where potions can be found.
* Sanity food can be a substantial boost if you need it. Try to use it in middle areas or the starting area rather than lost areas, as you'll lose less sanity from sitting for ten seconds. It doesn't interfere with your food buff.
* Every madness has counterplay, even if it isn't perfect. Leadfoot is about not moving when you don't have to. Split Personality is about moving away from walls before it procs and not fighting near walls when you can avoid it. Molten Feet is about triggering it safely each time it procs, or standing still when you can.
* If there's an elite with an ability that can't be fully countered (like Boundless Corruption with leadfoot, or the elite in the trade district with the channeled sanity drain), try to pull it with Gift active.