Familiar spinning hammer attack spam

[JusticeSeeker]

I've asked this over and over in game, scoured the forums and searched the web, and I still don't know how summoners can spam the familiar spinning hammer attack repeatedly.  I've seen it happen almost daily.  A summoner attacks something nearby with their familiar, and instead of doing anything themselves the pet will just spin in place repeatedly until the mob, or group of mobs, is dead.   I even had a player use it on me when I accidentally caught them in grasping roots and we had opposing faction on.  I died almost immediately.  As best I can tell there are only two spinning hammer attacks and both are situational, one works when held, the other when knocked down.  Yet I've seen a cat run in, spin spin spin combat ends, over and over in the last few weeks as I've played the game.  Am I missing something obvious or are these people exploiting a known bug that apparently is a well kept secret?  

[OddFinrir]

In the section where House and Alley Cat are, you'll see the first skill tells you it will use the skill "Roundabout" and do extra damage when the enemy is snared, which it tends to use more when the enemy is snared or their are  lot of enemies. It's an AI ability.