Impact and delay analysis is a combination of art and science together with lots of related experience.
There are best types of schedule delay analysis for different types of impacts and for trial, arbitration and negotiated settlement.
There is simply no better method for exposing the root cause trail
There are many types of Errors and/or omissions and many ways in which they can be the root cause
Before we begin any delay analysis, we must discuss the impact with project with the client team, all closest to the incident site and study ducumentation made available by the client, and make sure that we are applying the correct approach and methodology.
Before we begin any schedule impact-related incident we must make sure that all of the data and documentation properly relates the issues that impacted the schedule.