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What benefits would I get from lapping my CPU?

I'm not going to do it anytime soon, but i just found out about it. I can't really find any websites that list the benefits of lapping your CPU, but since it voids the warranty and could easily ruin the CPU, I'm wondering what the benefits are, or why people do it. Thanks

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1. When you buy a CPU the top surface looks smooth but there are microscopic pits in the surface. When you apply thermal grease the idea is to only apply a thin layer to fill the pits and the ones on the surface of the heatsink. Metal to metal is a better conductor of heat rather than metal to thermal grease or even metal to air! Lapping is the process of polishing the CPU surface so that it is microscopically flat. Of course, polishing mean removing the high spots, so you do lose part of the metal, but you do get better metal to metal contact. This site - http://www.frostytech.com/articleview.cfm?articleID=82 - says you can get an extra 10 degrees of cooling by lapping the CPU but most people seem to get between 3 and 4 degrees. There are risks doing this which is why it voids the warranty. Polishing is done by abbrasion which causes heat, so you could destroy the chip that way, and if aren't careful you can easily expose the core of the chip.
2. The "lapping" technique is usually applied to the heat sink...not the CPU! it removes microscopic scratches in the heat sink that would require thermal compound to "smooth" the surface to give as near to 100% contact with the CPU. lapping the CPU would remove the name and markings as they are "etched" onto the CPU surface..again to give as near 100% contact... IF you could achieve 100% contact between heat sink and CPU, theoretically you wouldn't need thermal compound! Lapping was popular years ago when you wanted to OC as there were no after market heat sink fans as there are today. when you lapped the old Aluminum heat sink (there were no copper heat sinks in those days!) you could get as much as 5C lower temps. and adding Arctic Silver 5 (arctic silver 3 back then!) could drop you another few degrees. It was a BIG deal back then! But today with far superior heat sinks that come lapped and polished there is little need for "lapping". Since only the CPU has any "etched" marks the reduction of temps would be unnoticeable if you lapped it!