Dave,
Your post is very clear and well stated regarding the effects of constructing seawalls and installing geotubes.
I do realize that many Gulf-front homeowners have much at stake, and many people, like yourself are helping search for the best possible solutions, from which all owners could benefit. I am very distant from having a solution, even though I think about it often. The one answer to which I keep coming back, is to let Mother Nature have her way. We humans tend to think that we are the most important things around. I see all of this panic, and installation of seawalls and geotubes. Within a few months, man will change that which Mother Nature took thousands of years to create. It just blows my mind. To me, that which makes the beach what it is, is the constant change. Maybe we all need to be open to inviting change into our lives and moving in harmony with nature. My personal opinion is that the Gulf front homes should not be allowed to rebuild once they are destroyed, not at the expense of everyone else and the Earth.
Just my $.02