[Bug-mit-scheme] imail question

[Julie Sussman]

I expect that this is a failure of my mental model,
not of imail, but ...

I filed a message in a new folder under inbox
(imagine inbox/foo).  I looked there, and the message
was there.  Emboldened, I filed a bunch more messages there
and deleted them (but didn't expunge them yet) from where
they originally were.

But when I looked in the new folder, only that first message was there.
I tried 'g' in case I had to ask it to find any recently added
messages, but nothing happened.  I was afraid to expunge the messages
from where they originally were until I knew they were really in the
new place.  Eventually, they appeared in the new folder.  What is this
time delay?  Is it necessary?  It is pretty scary, and requires
keeping track of when it feels safe to expunge the original messages.

Thanks for any explanation,
Julie