Abel made 9 rune word stealth armors in total, and one of which was for his own personal use. He wanted to swap out his Twitchthroe since that +25 casting speed was so attractive.
This speed was not the speed of magic pattern drawing, but the speed in which a spell took to form.
For example, the most powerful elite fire wizard spell "asteroid" took time to summon asteroids for attacks after the magic pattern was drawn. This whole process took 1.2 seconds. With this stealth armor, 0.3 seconds would be saved.
If wizards were fighting each other, even 0.1 seconds could dictate life and death, let alone 0.3 seconds.
Increasing casting speed was actually forcefully altering the law of the universe through the power of the rune word. It changed the speed of time, decreasing the time it would normally take to cast a spell.
