Delidding?

I always wondered why with the heat spread on the new CPUs gave off some very high temps I mean. You would think Intels heat spreader would work better than just mounting a heatsink right onto the dye. What are your views on this? 

I saw this video and now want more info about Delidding. 

http://www.youtube.com/watch?v=5fzhVt0TrVc&list=WLF9F682CBBA9E1F43

Dont do it with a blade, use a vice and a block of wood to avoide cutting tracks or scrtching the die 

youtube.com/watch?v=2eFzNpTOaOw

Also make sure the IHS is using a compound and not soldered on!