You know, this question is really asked way too much. This is long but a great article that says it very well. This is not really a good explanation for a HLE emulators or for Dolphin but rather what authors need to consider when making an emulator. Yeah its written by byuu but still worth reading.
http://arstechnica.com/gaming/2011/08/ac...mulator/1/
http://arstechnica.com/gaming/2011/08/ac...mulator/1/
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