Split grade printing will work in exactly the same way when contact printing.
One of the real benefits of split grade printing is the that you have the opportunity to burn and dodge on either hard or soft filtration and this can have a significant effect on the final result. Whilst it can be done when contact printing it is a little more difficult compared to when the image is projected. All it needs is a little practice and being prepared to use a few sheets of paper during the learning process.