Classification and taxonomy: hierarchy of normal central openings

All openings can be divided into big 3x3 parts (by height of pawn structures).

Definition 1. An opening is called Hippo for white (resp. black) when white doesn't move pawns to 4th rank (resp. black doesn't move pawns to 5th rank). A non-Hippo opening is called Normal when white doesn't advance pawns to 5th rank (resp. black doesn't advance pawns to 4th rank). Otherwise the opening is called an Advance variation. 

Example 1. Advance (white) vs Normal (black):

Definition 2. A normal opening is called Normal Central Opening for white (resp. black) when pawns moved to the 4th (resp. 5th) rank belong to files C, D or E.

There are 9 normal central opening hierarchies of height 2+2:

• 2Cc Symmetrical English
• 2Cd Anglo-Scandinavian
• 2Ce King's English
• 2Dc Old Benoni
• 2Dd Queen's Pawn
• 2De Englund
• 2Ec Sicilian
• 2Ed Scandinavian
• 2Ee King's Pawn

Example 2. The Amsterdam attack is normal central and belongs to the King's English hierarchy (pawn structure 2Ce). 

Very cool.

What would you rate the London system? Pawns on c3 d4 and e3.

London system is normal central (for white) belonging to 2D-hierarchy (or Queen's Pawn hierarchy). This is because we have the white D-pawn at 4th rank.  

Pawns on the 3rd rank don't count in this primary classification by hierarchies. The exact pawn structure for white is 2D1CE (here 1CE corresponds to pawns on c3 and e3).

Please do not adjust your brain...

I once read a book that was even deeper in the Hans Kmoch zone than Pawn Power is.

It was called "The grand tactics of chess, an exposition of the laws and principles of chess strategetics, the practical application of these laws and principles to the movement of forces; mobilization, development, maneuver, and operation" (that was just the freaking TITLE of the book) and was written in the 1800s by Franklin Knowles Young.

Which one is this?

That's a Hypertrophied Hippo met by an Advanced Oh-Crap-I've-Dropped-My-Queen formation.

And now, having didided the openings into big 3x3 parts, we are ready to sink that patzer Magnus into the abyss of oblivion...

Hans Kmoch was was very smart but was unable to unscience his knowledge to make it digestible. I have trouble reading his book to this day.

. I blundered by making white so cramped...and thus white would run out of moves without moving a pawn.

Ah... that brings back memories... most UNPLEASANT memories...

If only Patton had revised Young’s work. It would still be indecipherable, but at least it would be spiced up with lots of entertaining profanity.

LoL Indeed.  The Hypertrophied Hippo here is just the initial pawn structure (for white). For black, it's clearly an Advance Variation starting from 2...d4. 

The PSCC (pawn structure classification code) of your final position is 6d3ef2g1h. Its pawn height is equal to 6+3x2+2+1=15. 

The ideas and terminology here are very natural. Any little kid can easily distinguish Advance from Hippo as well as Central from non-Central. 

Magnus Carlsen is a great player but he doesn't work on the classification of openings. 

As David Hilbert said, a point of view arises only when the horizon of consciousness of someone shrinks to a single point.  Also, there is no authentic difference between practical and impractical. Everything, including the surrounding space-time, is an illusion created by the Matrix of our Local Multiverse. 

Not so easy brother. You then need to divide each section into 6x6 parts. That will really sink him DEEP.

Think the OP has missed his vocation. Knitting or stamp collection seem more suitable than trying to play chess.

D-Skye: Potentially, it could be more useful than ECO classification. Of course, U can consider that any kind of classification is useless for "practical" chess purposes.