Here's my take on the whole issue.
I'm not sure of this but this is just a couple of
observations I have made using lullaby extensively.
(Been using it a lot since I got it at level 15)
Every song pulses at every tick (6 seconds) as far as
I can tell. And lullaby/nod is no exception. I think
every time nod pulses the mob has to make a savings
check to see if it resists or not. Assume we have a
spell caster that resisted it, and then it begins
casting. If the casting does not take more than 6
seconds, there is no chance that nod will be able to
interupt it. Since NPC casters do not suffer the same
casting time limitations as PC casters do, most are
able to get a spell off before the next pulse of nod
and hence can cast without being interupted. However,
sometimes when the mob resist nod, it attacks first and
then cast. When this happens, the attack and the casting
might not be complete within 6 seconds so when nod pulses
again and the mob fails the savings, then it is nodded
and it's casting is interupted. This is what I seem to
observe a lot. YMMV.

Darrian Ashoka

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