Making a Single Core work on more cores would make the program execution a mess and cause slowdowns, the programs are compiled to work on a single core meaning it is not designed for any kind of multi-threading between multiple processors, a program can only benefit if its coded to do so.
:: System Specs ::
Operating System: Windows 7 Professional x64
Video Card: ATI Radeon HD 5770
CPU: AMD Phenom I X4 9550
RAM: 6GB DDR2
EXP Index: 999999.999999
Operating System: Windows 7 Professional x64
Video Card: ATI Radeon HD 5770
CPU: AMD Phenom I X4 9550
RAM: 6GB DDR2
EXP Index: 999999.999999