The ban hammer never crossed my mind and the big G don't seem to have a problem with any of the blogs.
Dupe content/unique content - if I worried about that too much I'd never try anything to find out what does and what doesn't work.

cguru:
Build a couple, if G bans you then learn from that and build the next couple a little differently until you find what does work but what I wrote at the start of this thread works.
I see the G spider crawling all over the blog all day long, maybe it sees the blog as an aggregator of everything related to the niche I'm targeting?
Who knows and to be honest, who cares? As long as G seems to like what I'm doing then I'll continue to do it
Seriously, set a couple up and see what happens. If G does ban you then no geat loss as it was only a .info domain you lose. At least you'll still have your Twitter followers to use with your next blog.
I guess that's the benefit of not relying in SE traffic and rankings when G bans you - it's no great loss and you can be up and running again within an hour with all the same traffic that you had before.
The more I think about this method - the more I like it