Okay, because I've been getting so many nasty letters about cheating, here's author comments straight from the speed runner's mouth.
Single-segment 0:14:26 by Ryan 'Benito' Bennitt.
Race: Argonian (Chosen for 50 Speed, 40 Intelligence, Alchemy Bonus)
Class: Assassin (Chosen for Speed +10, Intelligence +10, Alchemy Minor Skill)
Sign: The Steed (Chosen for Speed +25)
Take ring (all) from barrel outside
Talk to Sellus Gravius "Morrowind", "duties" (gives you gold)
Travel by siltstrider to Balmora
Go to Mage's Guild
Speak to Ranis Athrys, "join the Mages Guild"
Mage teleport to Caldera
Steal master's alchemy set from top of tower in Mages Guild
Go to Ghorak Manor, steal Orcish armour from crate on top floor
Sell Orcish Greaves & Cuirass to Creeper
Go to Verick Gemain, Trader, Purchase Warhammer of Wounds, Amulet of Recall, and sell unwanted items
Mage teleport to Sadrith Mora
Mages Guild, Purchase 10 Corkbulb, 10 Racer Plumes, 10 Trama Root from Tusamircil
Go to Imperial Shrine
Purchase 5 Chokeweed, 10 Saltrice from Scelian Plebo
Purchase 130 Ash Yam, 65 Bloat, 5 Guar Hide, Divine Intervention Spell from Aunius Autrus
Assign quick keys: Warhammer (1), Alchemy (2), Recall (3), Divine Intervention (4)
Create and drink Fortify Intelligence in batches of 5
Create Levitate potion
Levitate to Apothecary, Purchase 7 Shalk Resin, 5 Kagouti Hide from Pierlette Rostorard
Purchase 2 Vampire Dust, 60 Bloat from Anis Seloth, Alchemist
Create and drink Fortify Intelligence in batches of 5 from Ash Yam & Bloat
Create 2 Fortify Strength & Fortify Health from Ash Yam, Vampire Dust, Shalk Resin
Create 5 Fortify Luck from Guar Hide, Corkbulb
Create 5 Restore Health from Corkbulb, Saltrice
Create 5 Fortify Speed & Restore Fatigue from Kagouti Hide, Shalk Resin, Saltrice, Chokeweed
Divine Intervention, go to Mages Guild
Mage teleport to Ald-ruhn
Purchase 3 Mark Scrolls from Tanar Llervi
Assign quick keys: Scroll of Mark (2)
Levitate North-East to Vemynal, Mark outside, get Sunder, Recall
Levitate South-East to Dagoth Ur, Mark outside
Levitate South to Odrosal, get key from Dagoth Odros, get Keening, Recall
Run through facility, Mark Facility Cavern
Kill Dagoth Ur, enter Akulakhan's Cavern
Strike Heart with Sunder
Destroy Heart with Keening, equip other weapon to avoid death
Recall to Facility Cavern, speak to Azura
Just discovered that you don't actually need to join the mages guild. Ingredients and scrolls be bought without being a member The jump down the tower in the Caldera Mages Guild can be done without getting stuck on beams (oops) on the way down. Hurts a bit, but you survive. I get stuck on a couple of bits of scenery in Caldera, furniture in the Ald-ruhn Mages Guild, and on walls/doors/scenery inside the various fortresses inside the Ghost Fence. In Sadrith Mora, Pierlette Rostorard, Apothecary, could create and drink Fortify Speed/Damage Fatigue/Restore Fatigue potion once ingredients purchased, resulting in quicker trip to the Alchemist. Might not need quite so many Ash Yams and Bloat, it depends on the early luck of the draw when creating the intelligence potions, and how powerful you want your Fortify Speed to be. Could combine Fortify Luck and Restore Health (Guar Hide, Corkbulb, Saltrice) into one potion. Could combine Fortify Health, Fortify Strength and Fortify Intelligence (Ash Yam, Vampire Dust, Shalk Resin, Bloat) into one potion. Might need only 5 Shalk Resin, 3 Kagouti Hide, 3 Chokeweed, saving one barter and a few clicks. Made a few mistakes during the alchemy section, taking off clothes when a potion didn't pick up, selecting wrong ingredient, deselecting the apparatus. Don't need to bother creating so many potions (especially levitation).
First Mark outside Vemynal might be better placed west of Dagoth Ur (if that turns out to be closer). Second Mark in Dagoth Ur crater could be placed while on the move rather than descending right into the crater (but be careful as I've ended up either stuck on scenery or in the lava while attempting this). Third Mark should be better anticipated and placed while on the move. Equipping and using Amulet of Recall should be better anticipated.
Don't need the key from Dagoth Odros, could simply buy a Scroll of Ondusi Unhinging from Tanar Llervi Don't need to drink all the potions at the end, but you must ensure Keening doesn't kill you. It took me too long to line up my aim on the heart (but there's nothing worse than striking with Sunder to find you're too far away). I go a bit psycho with Keening on the heart (However, in previous runs I have backed off too quickly and failed to destroy it). I reckon this run can be done in less than 14 minutes.