The problem is you have to be using the new blogger, and there seems to be some access restriction for existing Bloggers.
I have just tried that work around, and it didn’t work for me, so maybe Google have closed that loophole.
The thing I am interested in most is this note Amit made:-
Now the best part – even if you move from abc.blogspot.com to abc.com, your old links would still work and Google [via a simple DNS settting] will redirect the traffic to your new URLs. And the addresses of your blog posts saved on Digg, Del.icio.us would also work.
Having already moved my blog from blogspot to my own domain, I would appreciate a rock solid redirect with a 301.
Whilst I have previously mentioned Google seem to be following meta redirects, that might not be 100% reliable, and that doesn’t account for other search engines.
Yahoo and MSN seem to have kicked my old blogspot with the meta redirects out of the search index, but are not passing on old link equity in the way Google does.
For over a year before the redirect from blogspot I was holding top3 on all 3 major search engines.