I haven't ever had that happen to the outer CV.
Yes, it is inside the trailing arm and doesn't see that much debris, salt or road grime as compared to the inner.
Still, if that was my issue i would use my 3/4 impact, knock off the axle nut, slide the stub through enough to cut it off and replace.
Of course, I would have tried Scotts whackin' technique first.

I haven't had any issues when using these:

http://insyncro.spaces.live.com/blog/cns!A35A8130F909DA96!575.entry

dylan

________________________________
From: Mike S <mikes@flatsurface.com>
To: dylan <insyncro@YAHOO.COM>
Cc: vanagon@GERRY.VANAGON.COM
Sent: Tue, December 29, 2009 8:25:42 PM
Subject: Re: triple square axle bolts information for newbie

At 08:05 PM 12/29/2009, dylan wrote...
> worst case, if the bolt is that bad, just cut the head off with a roto tool and slide the CV over the headless bolt.

Good luck doing that on an outer CV bolt head, which sits well recessed inside the swing arm. Maybe a long, high quality drill, but a socket is cheaper and probably on hand. CV bolts are (or should be) hardened, grade 12.9.

The 12mm socket solution obviously worked, but I'd think that using a top-quality socket would provide an even better chance of success - better chance of digging the socket edges into the hardened CV bolt. Throwing away a $5 socket is nothing compared to the potential grief.