(petitioner purchased poultry processing facilities in 1995 for over $27 million and in 1998 for almost $11 million; purchase agreements included purchase price allocations for acquired assets as agreed to by parties, with most of them being listed as real property depreciable as 39-year, non-residential real estate property using the straight-line method; in 1999 petitioner had CPA firm prepare "cost segregation study" which would appraise the real estate component by component, resulting in reallocation of purchase price of buildings to shorter-lived assets, and petitioner then filed amended return changing depreciation method used on buildings to account for shorter lives of components and generating additional depreciation deductions of $5.3 million for years in issue (due to use of double-declining balance method over 15 and seven year lives for the components; government disallowed any modification to original purchase price allocations on the basis that I.R.C. Sec. 1060(a) mandates that the allocations specified in the purchase contract controls; petitioner claimed that I.R.C. Sec. 338(b)(5) allows use of residual method; court agreed with government and noted that allowing subsequent change could put government in "whipsaw" position; residual method only available where contracting parties do not agree in writing to allocation of consideration of acquired assets (citing West Covina Motors, Inc. v. Comr., T.C. Memo. 2009-291)).