A method of conducting timing analysis on an integrated circuit design includes performing a first routing operation on the design to generate a first routed design that includes redundant vias, and storing the first routed design in a first design database, and performing a second routing operation on the synthesized design to generate a second routed design that does not include redundant vias, and storing the second routed design in a second design database. Then, extractions are performed on the first and second designs and delay calculations are performing on the first and second extractions files. The first and second delay calculations are compared to determine a delay difference between the first and second designs and timing analysis is performed using the delay difference.