I agree there is no silver bullet. Schuster will make a difference, but replacing Harper with Koula, Croker with Lawton and one of the props for Tuitavake (which I want to see, personally) will not change the outcome of the last 2 games one bit.
It's pretty clear to me that we have a system issue. Without getting too technical/philosophical, have you ever heard of the 94% rule? I read about it a few weeks ago, and the theory goes something like 94% of the results we experience in the workplace, both good or poor, are a function of the systems and processes in which people work, not the efforts of people. The easy path is to focus on the 6% but in reality it's the system that is likely the problem. That is no doubt what Des and the coaching staff, as well as the players, will be focusing on.