Improved Fireball

Improved Fireball is a mage talent that reduces casting time of the Fireball spell by 0.1 seconds per rank, up to 0.5 seconds at rank 5. This talent significantly increases the DPS of Fireball, making it a valuable talent for mages that use the spell frequently.

Example
The following example uses Fireball rank 13, with a 3.5 second cast, 633 - 805 damage done, and a base spell damage coefficient of 1.0 without talents.

(633 + 805) / 2 = 719

On average, this is 719 average damage done per hit.

719 / 3.5 = 205.4

Dividing by cast time, the spell does 205.4 Damage Per Second. With 5 points in the talent, but with no spell damage:

719 / 3.0 = 239.7

With no spell damage, the talent gives a boost to Fireball Damage Per Second of 34.3. Add in 500 spell damage:

719 + (500 * 1.0) = 1219

The average cast now does 1219 damage per hit without the talent.

1219 / 3.5 = 348.3

The spell now does 348.3 Damage Per Second without the talent. Now take 5/5 Improved Fireball:

719 + 500 = 1219

The average cast now does 1219 damage per hit.

1219 / 3.0 = 406.33

Fully talented, the example gives 406.33 Damage Per Second, over 348.3 without the talent, a Damage Per Second increase of 58.033 if you have 500 spell damage.