Game Mechanics: Cowardly Enchanter pets

[Splorf22]

I've been trying to get my monk a Pearlescent Mask today. Kedge of course is annoying, but I was surprised by this. Now I have known for a long time that pets won't attack if you resist spells. But I am surprised that Shellara could actually land a dot on me without my pet assisting.

[Fri May 09 19:47:18 2014] Lobober says 'At your service Master.'
[Fri May 09 19:47:19 2014] a gloomwater mermaid begins to cast a spell.
[Fri May 09 19:47:21 2014] You begin casting Speed of the Shissar.
[Fri May 09 19:47:21 2014] Your Staff of the Serpent begins to glow.
[Fri May 09 19:47:27 2014] Lobober's body pulses with the spirit of the Shissar.
[Fri May 09 19:47:29 2014] Targeted (NPC): Shellara Ebbhunter
[Fri May 09 19:47:29 2014] Right click on the NPC to consider it.
[Fri May 09 19:47:29 2014] Shellara Ebbhunter begins to cast a spell.
[Fri May 09 19:47:31 2014] You begin casting Pillage Enchantment.
[Fri May 09 19:47:32 2014] You can't use that command while casting...
[Fri May 09 19:47:32 2014] You can't use that command while casting...
[Fri May 09 19:47:32 2014] You feel the pain of a thousand stings.
[Fri May 09 19:47:34 2014] Shellara Ebbhunter begins to cast a spell.
[Fri May 09 19:47:35 2014] Your spell is interrupted.
[Fri May 09 19:47:36 2014] You resist the Flame Lick spell!
[Fri May 09 19:47:36 2014] You can't use that command while casting...
[Fri May 09 19:47:36 2014] You begin casting Pillage Enchantment.
[Fri May 09 19:47:37 2014] You can't use that command while casting...
[Fri May 09 19:47:38 2014] Shellara Ebbhunter begins to cast a spell.
[Fri May 09 19:47:40 2014] Your Fetter spell has worn off.
[Fri May 09 19:47:40 2014] Shellara Ebbhunter feels very dispelled.
[Fri May 09 19:47:41 2014] You resist the Careless Lightning spell!
[Fri May 09 19:47:41 2014] Shellara Ebbhunter tries to hit YOU, but YOUR magical skin absorbs the blow!
[Fri May 09 19:47:41 2014] Lobober tells you, 'Attacking Shellara Ebbhunter Master.'