Several questions about Aran

I have a few questions:

I still don't get how the "upgrade skills" Full Swing and Overswing get calculated...

1. Is this the correct way:

Job / Skill	Double Swing	Triple Swing	Final Blow	Info
1st Job	140% x 2	-	-	-
2nd Job	140% x 2	250%	-	-
3rd Job	250% x 2	600%	-	With maxed Full Swing (+110% x2 / +350%)
4th Job	420% x 2	840%	700%	With maxed Overswing (+170% x2 / +240%)

2. Can anyone explain that to me too:

Why would Final Blow (700% damage) be a usefull skill if you can just chain another Overswing, that does more damage (420% + 420% + 840%)?!?!
Or does Overswing something else then just 700% damage?

3. In what situation would the 3rd job skill "Whirlwind" usefull in -ANY- way?

I've been trying to think of situations, but I can't seem to find any... Anyone who has any idea's for what it could be used for?

4. About Combo Tempest

1	1210% damage	10 Seconds	Attacks 15 enemies	Attacks 4 Times
30	1500% damage	40 Seconds	Attacks 15 enemies	Attacks 4 Times

What does it do for 10 Seconds ~ 40 Seconds?!?!?!

1) After full swing, the damage is exactly what it says in the skill window. Same thing for overswing...just double swing hits twice with max full swing, while both double and triple swing hits twice with overswing.

2) Over double swing = 340% damage.
Over triple swing = 480% damage.
Level 1 final blow = 410% damage.
Max final blow = 700% damage.

How is it's use not obvious?

3) It isn't useful. Ever.

4) It freezes monsters/makes them ohkoable for the amount of time listed.