While I concur with the Gap Band's origination of this particularity of the phrase...
Its came to be in more modern times via the "skilliage fo'realiage" of Hip-Hop icon E40 whom originaly dictated the root of Fo'Sheezy, which then evolved as it went to south to LA into "Fo'Shizzle"... indeed history is written "via ferus victorus". However it is always evolving to newer heights.
"fo' shizzle my nizzle" is now "Ph'zz'zz'm'z'lel'le"
But of course my dear comrade!