I've seen snipits of people discussing this--saying it operates too hot while the lid is closed. I've also read how people love to use it connected to external screen while lid is closed... As I do to keep dust out of the keyboard, etc. I don't do much other than email, browsing, and never video or anything requiring lots of computing power while the lid is closed. Is it still better to keep the lid open? Does it matter much while only doing simple tasks? Just want some simple clarification. Thanks guys.