Dramatic increases in design complexity and advances in IC manufacturing technology affect all aspects of circuit performance and functional correctness. As interconnect increasingly dominates delay and power at the latest technology nodes, much effort is invested in physical synthesis optimizations, posing great challenges in validating the correctness of such optimizations. Common design methodology delays the verification of physical synthesis transformations until the completion of the design phase. However, this approach is not sustainable because the isolation of potential errors becomes extremely challenging in current complex design efforts. In addition, the lack of interoperability between verification and debugging tools greatly limits engineers' productivity. Since the design's functional correctness should not be compromised, considerable resources are dedicated to checking an ensuring correctness at the expense of improving other aspects of design quality. To address these challenges, we propose a fast incremental verification system for physical synthesis optimizations, InVerS, which includes capabilities for error detection, diagnosis, and visualization. This system helps engineers to discover errors earlier, simplifies error isolation and correction, thus reducing verification effort and enabling more aggressive optimizations to improve performance.