Endurance points is an abstract measurement. Velvet just saw this magician lift a full grown man into the air with strings, attacking from every angle. 

Her through process would be : "Even with Twilight Steps, that's an omni-directional attack... There's no dodging that. And the blacksmith dude is trapped just from one attack. If I got caught, being far less physically fit than the average man, much less a blacksmith, there's no way I'd escape being strung up and killed."