There was never evidence to indicate that the results of previous work were as successful as had been hoped. It was anticipated that since it dealt with group-wise registration (and globally optimal models), its results should clearly be better than those obtained from pair-wise registration under similar conditions. This approach came with an extra cost to make things even tougher. The process which offered little improvement was far slower and the results were not superior by any noticeable measure. In fact, it is possible that the results were partially biased - not positively, but rather negatively, due to few of the conditions set for the experiments.
Back at the start, circa October 2004, impending experiments aimed to disprove the claim that the conditions and choices made were the cause for any apparent advantage. They just as well aspired to increase apparent gains of group-wise registration - something which was not yet evident at the time. Answers as to why this was so will be given in Chapter .