Santorum has beaten Newt in every state since Florida, save Nevada. So what you are saying is that Newt is splitting, not Santorum.
Unless you believe the tail should wag the dog.
No sense arguing in circles since it’s unlikely we’ll agree on the reasons that caused the fracture.
The assumption that Rick would benefit from Newt’s departure is based on weak data. Also, Newt hoped to derail Romney’s nomination by forcing a brokered convention.