It is known that the PhD would make an original contribution and/or advance knowledge in a given field. In my field ( Computer science), there are various PhD contribution that combine methods to solve a problem.
In short, my question is: What are the conditions to develop an original/novel method for a contribution of a PhD by combining two or more methods that had never been combined before. I mean the case where we combine method A and method B to solve a problem T where A and B has never been combined before to solve T.