Hello, I own and run www.creoleproject.com - ie where you found the article on Bousillage construction. I am happy to see that you found it informative. The gals that put it together are very thorough and one of their husbands if a friend of mine and accomplished timber framer and preservationist, John Blokker. I envy your project, it sounds like a lot of fun.
I was contacted by J about this conversation and have briefly skimmed through it. I wanted to make a few comments if I might.
First, hewing and sawing is not so bad. You are not looking for perfect timbers merely functional ones. What I mean by that is that pretty is only so useful in keeping water off of your head and pretty makes modern construction easier but has little effect upon your needs. Timber framing and log building techniques do not care about pretty so long as the timber works for the location. Joinery methods are rarely affected by winding, tapering, irregularities etc.
Also, Cypress and Pine are by FAR the easiest timber to hew for construction. I will not personally set to building timber structures from anything outside of the conifer family. They are generally straight, small branches (small knots) and easy to work.
Functional open style pit saws may be purchased from Frog Tools or I believe Thomas Flynn & Sons in Sheffield England may still have one for sale as when they custom made one for me they made a small production run. Overall, invest in good tools whether in terms of money or in sweat equity cleaning up good old ones.
The second thing to note is that Bousillage serves two main purposes - It is a quick and dirty means to achieve separation and thermal mass. It is not rocket science. Mud/clay/sand is still earthen and will break down with time / exposure. Sand is the least important component of bousillage. The real reason I was eager to post Laura's research upon Bousillage was primarily because it dispelled many myths about the careful and tedious preparation of such.
Fibrous reinforcement in bousillage or adobe is a must but it is not a recipe worth being too picky over. Early buildings are composed of materials that were on hand - do the same. The Bousillage needs protection from the elements to last, consider lime wash or much better still is wood clad of any fashion.
Have you considered roofing yet? That would be a good place to put any white oak you may have - otherwise Cedar, Cypress or as a last resort earthen, thatch or Pine.
In regards to foundation, it's tough to beat the advantages of a raised structure for cooling but also for longevity. In a wet climate such as South Louisiana, raised structures last far longer as air is allowed to circulate under and around the structure keeping mold / mildew / rot to a minimum.
I have not yet set a date for it yet however I will have a lumbering and building class coming up at LSU this year. Following the web site will keep you informed upon that if you are interested.
Regards and much luck and learning on your project.