This is a keen observation that make a surprising conclusion. I made the same observation but had a completely different reaction. The stuttering was actually

This is a keen observation that make a surprising conclusion. I made the same observation but had a completely different reaction. The stuttering was actually a motif to show this are pictures of different laptops of real people. It also completely tied into the music which was of a stuttery and impactful tone. It was obviously an intentional technique. You will notice that the laptops were also scuffed and looked used. The whole ad was about how personal a macbook is to its owner. I think apple have been concerned mac's are now so 'mainstream' they want to encourage the view that you are your macbook.