The delta wing does not reduce the effects of passing through (or approaching) the sound barrier, the sweep of the leading edge does that. Delta wings are used because they generate more lift once you pass 1.2 mach, they are how ever much worse than normal wings below 0.8 mach, this is why the more advanced planes went to swing wings, so that you can be efficient at both speeds.

The "buffering" is caused by the shock waves of compressed air hitting the control surfaces, ie tail, wings and what have you.

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The Muslim Brotherhood “must understand that their work in America is a kind of grand Jihad in eliminating and destroying the Western civilization from within and ‘sabotaging’ its miserable house by their hands..." — Mohamed Akram. http://jihadwatch.org/