User blog comment:Wadem18/Anakin vs Grievous/@comment-5461477-20130216130855/@comment-4185015-20130312192228

He says "You're shorter than I expected", showing he only expected something from him. If he had seen him, he would have said, "You're shorter than I remember". He was only going by what he had heard. Plus, Anakin looks different heightwise to other people because they are small, and Grievous is very, very tall.