I don't beleive that would ever happen. Once the DC crowd has both a sales and income tax, they will never get rid of either one. The ONLY practical way to replace all our other taxes with a sales tax is to do it all at once in a single bill. Once the income tax, the tax code, and the mechanism to enforce it is gone, and we are actually running without one, then it would be fairly easy to get a consitutional ammendment to prevent a new income tax.
We'll be lucky if we ever get a chance to radically change the tax structure in this country. We better get it right the first time, because it will probably take another 100 years to do it again.
So lets just suspend any revenue collection to pay our troops while they are getting the whole sales tax thing working efficiently. All we who support the FairTax heard from the naysayers was that we can't make the sudden change and keep thing like military paychecks running smoothly (like they were ever that, as a vet myself) along with other enumerated power responsibilities.
So now that someone comes along with a plan to make that transition, we have you now saying you want just the opposite. This is a one time deal, just a better way of making a smoother transition from the monster that was created over a very long time.
The other part of making it a reality is to primary out those career politicians whose oxes would be gored in the process of bringing this to a reality. This is our government and it is our responsibility to clean up what we have allowed it to manifest itself into by being lazy about keeping our representatives accountable.