As was mentioned above, I have not used this method on a large project , only on my 18 inch blocks for my current QAYG project. All 25 blocks stood up to quilting without anything shifting and came out beautifully crisp and flat.
As someone else mentioned, even if you only used this method for smaller projects, think of the basting spray that saves you to use on your larger ones. Every little bit saved adds up , and being on a fixed income , I love knowing I can save in one area to give me more to use in another !