I have studied numbers of errors caused by using the Copy-Paste method and can assure you that programmers most often tend to make mistakes in the last fragment of a homogeneous code block. I have never seen this phenomenon described in books on programming, so I decided to write about it myself. I called it the "last line effect".
At the beginning of the computer era the system designers came from the world of hardware and it is noticeable. In hardware there are many working elements that can operate in parallel and most times at different rates of operation. This requires hi degree of accuracy in system timing. Chip designers count the number of transistors between two elements to make sure that the Operation Flow is maintained.