The results of GE 2011 spoilt PAP's original plan. LKY, GCT and WKS were never meant to step down from the cabinet. They were to remain in cabinet actually with their intended new titles being Senior Minister Mentor (for LKY), Minister Mentor (for GCT) and Senior Minister (for WKS).
The inside story was that in view of the negativity towards LKY's silly remarks of "live to repent", he was to step down from the cabinet to appease the people. But to save his face, it can be he alone to be ousted from the cabinet, and hence GCT was made to accompany him. GCT however protested and a compromise was then reached to confer him the stupidest title in the world of Emeritius. The record for the stupidest title in the word before this was none other than Minister Mentor. Had it not been for the poor GE results, LKY even after he's dead would be conferred the title of Eternal Minister.