clock nets routing

We're recommending that clock nets be routed during CTS because it enables CTS to adjust the clock network after detail routing the clock nets to compensate for differences in estimated route topologies and associated parasitics vs. what routes are actually created by the router during CTS. A good reference to look for flow recommendations like this is the "Foundation Flow" which was released in 8.1. Here's an excerpt from the Foundation Flow Flat Implementation User's Guide ( http://sourcelink.cadence.com/docs/files/Release_Info/Docs/flatImpl/flatImpl8.1/flow.html ): "Set CTS options; the recommendation is to route the clock nets during CTS. If some signals should not be routed, set the clock nets option to false and use 'RouteClkNet true' in the spec file. set vars(route_clock_nets) true ; # Route all clock nets during CTS" Hope this helps, Bob