1. A method for performing verification, said method comprising: receiving a design; building for said design an intermediate binary decision diagram set containing one or more nodes representing one or more variables; first case-splitting upon a first fattest variable from among said one or more variables represented by said one or more nodes by setting said first fattest variable to a primary value; first cofactoring said intermediate binary decision diagram set with respect to said one or more nodes using an inverse of said primary value to generate a first cofactored binary decision diagram set; second cofactoring said intermediate binary decision diagram set with respect to said one or more nodes using said primary value to generate a second cofactored binary decision diagram set; and performing verification of said design by evaluating a property of said second cofactored binary decision diagram set.