[NCLUG] Debian wheezy crypto install - skip the 6-hour erase?

[John Gilmore]

I just had a install fail on me - but AFTER the six hour erase of the
encrypted hard disk. Is there a way to skip that step the second time
around?

How about skip it the first time through- the hard drive contained
encrypted data to begin with, so is there really any point to erasing it
anyway?

And on a not completely unrelated point - having restarted the install, is
there a safe way to abort the erasure and continue the install?

I just really don't want to wait ANOTHER six hours before I can setup the
LVM (AGAIN!) and try to install packages again. If there is a shortcut,
maybe I can get the install completed and my home directory restored before
I go to class tomorrow morning. It'd be nice to have my laptop with me.