I just blitzkrieged my system--can someone explain why?

["STeve Andre'" <andres_(_at_)_msu_(_dot_)_edu>]

OK, I am confused.

I just trashed my hard disk, and I'd like to know if I'm ignorance on how the
dd command works or swapping works, or if I found a problem somewhere.

Running -current of 10/27 on a ThinkPad 1480i with a 6.4G disk.  I wanted to
put the latest snapshot on, so got the 10/29 version.  Thinking I could avoid
using another floppy, I thought about putting the image on to my swap partition
and then booting off wd0b.  As I think about this, it's occurring to me that my
using swap in such a manner lead to my disaster, even though I have 192M
ram.

I did I a

        dd of=/dev/wd0b if=floppy28.fs bs=1024

Upon trying to reboot I got a "Bad Magic" error.

OK, I say to myself, I didn't have anything useful on this disk so started the
install process again, using a floppy.  I said I would use the entire disk for
OpenBSD; all the numbers for fdisk looked correct.  Disklabel however said
that I had three partitions, a, b and c, all at 1.4M, the size of a 
floppy.  The
"free sectors" count was 12,659,157 which is about right.  Doing a "D" to
set the label to it's default worked.  I'm continuing on with the install, and
all looks as it should.

But I have two questions:

1. Was the dd command I did instant death on a live system, even with a
lof of ram?  I do get the feeling that I did a Dumb Thing, and disrupted
whatever structure was laid out for swap?

2. What caused disklabel to think that all three partitions were the size of
a floppy?

--STeve Andre'