Merde and ... that Shoe Polish

There is a coarse popular phrase that is (or at least once was) used to describe an ignorant person, to wit:

  "He don't know S@@T from Shinola".

Whenever I hear the phrase, I'm reminded of the classic George Carlin routine which informs us of the membership of S@@T in the 'Seven Words you can't say on the radio'. I always laugh when I recall how, after talking about 'S@@t', he mentions the popular phrase, then follows up with "I always wondered how the Shinola people felt about that". Comic compassion I suppose, but I'm also called to mind of the old adage that bad publicity is better than no publicity, something Ann Coulter and Michael Moore, at least, have in common.

There is a variant of the phrase under discussion, where the possessive is used, as: 
 "He don't know his _____ from _____"
  "He don't know his a@@ from a hole in the ground" (or from his elbow).

(Of course substitute the feminine gender if you prefer, as we know they are not delicate creatures, but rather robust, and, one hopes, lusty, at least sometimes).

Anyway, the structure of the phrase has always charmed my mind, so I offer these contributions:

"He don't know his epistemology from his episiotomy" (for Interns of Philosophy)
"He don't know Phillip Roth from David Lee Roth"
"He don't know Tadasana from Savasana" (for Yogis/Yoginis)
"He don't know pince-nez from Nez Perce" (for sight-impaired ethnologists)
"He don't know thread-safe from thread-bare" (Java nerd who is innocent of sartorial skill)
"He don't know David Ricardo from Ricky Ricardo"
"He don't know Hamas from Hummus" (and obviously lacks a taste for international affairs)
"He don't know Percy Faith from Percy Sledge"
"He don't know Pepys from Pepin" (but at least he has a passing understanding of European culture and history)
"He don't know his Ganesh from his Ganache" (for a clueless caterer at a French Hindu wedding)
"He don't know his Baltic from his Balkans" (and therefore joins the majority, we would estimate)
"He don't know his Schoenberg from his Strindberg"
"He don't know his Lunch Ladies from his Ladies Who Lunch"
"He don't know his George Grizzard from his George Peppard"
    (and is therefore hoist on his own petard)
"He don't know his Transfiguration from his Transubstantiation" (for Catholics)
"He don't know Longoria from Louganis" (you know, 'which team' are you on?)
"He don't know his 'Large Icons' view from his 'Thumbnails' view" (obviously a Windows user)