In January ('05), I had two procedures; septoplasty and ESS
(specifically, maxillary  antrostomy).  During recovery, I developed a
hole in my septum.  I could hear whistling which prompted me to do a
little more research and found that a hole can cause this.  I can
actually see the perforation; I estimate that it's a bit smaller in
diameter than a q-tip end (don't worry, I'm not stuffing q-tips up my
nose for reference).  My ENT thinks there's a good chance it will heal
on its own and close.  I am VERY sceptical about this.

1) Is it fairly common for a perforation to heal on its own?

2) How do they develop?  Did I do something wrong during recovery, did
the surgeon make a mistake, or is it other factors?

If you have any anecdotal information about these perforations, please
pass it on to me.