According to your link it states 2 feet or higher, that sounds pretty general to me and is merely a starting point/guideline. Different surround speakers will require different placement ie dipole ,direct etc. Dolby has entirely different suggestions. If that is what works in your room that is super but I am not about to place my speakers where they don't sound as good just because I am told that is where they have to be.

DOG is GOD spelled backwards.
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