Whirling Defensehttps: https://wiki.guildwars2.com/wiki/Whirling_Defense
The main problem regarding Whirling Defense is the "sitting duck" stance. It is the only skill of it kind who make the player to be a sitting duck. Other classes can move when they do similar skill. Also the area for this one it is only 150 units. Every time the enemies just move 2 steps and then they just are looking at you how you spin like a fool ... almost they laugh on the whole period of your spinning. After you finish this show/spectacle (we must mention that we can't stop doing this ... the only way is to waste a dodge or another skill) they walk gentle near you and start again what they did before you use WD.
I must mention that even when you put down someone with WD, you can't stomp him till the skill didn't get his whole spinning, again you must wait or use a dodge (in this way you move away of your downed enemy) or another skill and after that you can stomp him ... ofc if the enemy is still there.