A variation on theTotal Cost Method/Approach known as the "modified total cost method" still enjoy some level of success. This modified version of claim quantification addresses the shortfalls of the total cost approach by attempting to segregate the aspects of the work affected by the project owner's shortcomings. Further, the modified approach does not blindly accept the contractor's pre-bid cost estimates or the contractor's as-performed job cost records. - read: http://www.lexisnexis.com/legalnewsroom/real-estate/b/real-estate-law-blog/archive/2010/09/15/total-support-for-the-modified-total-cost-method-pricing-of-claims.aspx#sthash.Wt2mrML3.dpuf
Although the best method of claim quantification remains the maintenance of segregated cost records and delay fragnets in the schedule by contractors for any changed work, it is reassuring to know that the modified total cost method is a viable alternative when maintaining such segregated records is not possible.