MissionCleanup and delete

Hello!

I tested a spell resource the other day, and I met these lines
( I forgot who is the author, but thanks for this :) )

%p = new Explosion() {
  [ datablock... ]
}
MissionCleanup.add(%p);

and

%p = new ParticleEmitterNode() {
  [ datablock... ]
}
%p.schedule(2000,"delete");

What is actually the appropriate way to effectively clean an object when finished with it?

As far as I can see it, the code:

%p.schedule(2000,"delete");

induces a call to the object's destructor after 2 secs, whereas the code:

MissionCleanup.add(%p);

will clean the object when leaving the mission.

Does this make sense or is it completely wrong?

Now, supposing I call

%p.schedule(2000,"delete");

but the exposion is long and is still being rendered at that time, what will happen?
I will try anyway ^^

Thank you by advance for any info.

Cheers,

Isi