SetEffectLifeMode seems quirky??

Here is the issue

I create a bullet with a particle effect attached to it.

I use
%bullet.setLifetime(1);
to destrtoy the bullet after 1 second.

I thought this was also deleting the attached effect untill I noticed that the count kept increasing. The bullet and particle would disappear but the object count would only go down by 1.

so
I added this to the particle:

%smoke.setEffectLifeMode("KILL",.5);

this works only because I kill the particle before the bullet lifetime triggers.



If I set the value to anything longer than the life of the bullet, the particle still disappears but doesnt get removed from the object count.

example
%bullet.setLifetime(1);
%smoke.setEffectLifeMode("KILL",2);
Doesn't work.

but......this does work!
%bullet.setLifetime(1);
%smoke.setEffectLifeMode("KILL",0.5);


Is this they way it's supposed to work?