Don't want to look for the hair in the soup, especially because I generally agree with what you are saying.

1. Either you take an area the size of France out of the presently farmed area in order to accomplish this goal (which is pol. difficult (!) in an environment of rising produce prices)

OR

2. You create new agricultural area the size of France. This is theoretically possible - just wondering tho, where are you planning on getting the water for it?

OR
3. You could create a Carbon Tax in Kind (i.e. payment to be paid in carbon) to be placed on all agriculture and then systematically build up the soils of run down areas with the procedes...

I could continue my comments, BUT..
btw, wouldn't this post be more appropriate on a drumbeat?
Cheers, Dom
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Just remember the Golden Years, all you at the top!

The great thing about the EPRIDA model of production is that it DOES NOT take land out of production-- it actually makes the land more productive, by generating carbon negative fertilizer to go along with the biofuels:

http://www.eprida.com/home/index.php4

So, not only do you sequester carbon, you do it in a way that makes the soil more productive, long term, and frees farmers from the need to buy fertilizers generated with fossil fuels. The Amazonians were doing this thing 4000 years ago, just not generating the biofuels along with it.

Yes, terra preta was and is a great method.
A real silver bullet.
I'm quite curious how modern man will screw this one up.

(who, me? negative? naaaaaaaa......)