SOME five hundred years ago there lived this renaissance guy, bent on looking at things in a new light, as was the fashion, and being a Shatranj player, he looked a lot at Shatranj. Suddenly it hit him: the bishops were crippled.
We agree, they weren't even bishops. They were "fils". They could jump diagonally to the second square, leaping the intervening one. They had only seven squares in total. They could never attack one another. Our hero suddenly realized they were pathetic.
And so was the "firzan" or minister, that had a one square diagonal move and was the only piece a pawn could promote to.
There were a couple of additional rules that we would consider rather odd nowadays - they don't matter here. What matters is that our hero came to the conclusion, obviously, that the whole concept needed rethinking.
So he did: he liberated the fils and made them bishops, and gave pawns the right to promote to any piece.
In this environment the firzan of course became even more pathetic, and here he made the boldest step, therewith implying Grand Chess in the concept.

Combining powers
He combined the powers of bishop and rook and turned it into a piece of unprecedented strength: the Queen.
This was a very bold step indeed. We look upon the queen as well within the boundaries of balance, but 500 years ago its power must have seemed unbridled.

Two other combinations
He may well have been aware of the rook-knight and bishop-knight combinations, but straight and diagonal are clearly the first movement options to be considered, so the choice that the 8x8 board forced him to make was logical.
And to be fair: players weren't quite ready for Grand Chess, back then.

Rook development
Rook development constituted a problem. The problem with rooks is that they are obstructed by their own pawns, unlike bishops and knights. And precisely the rooks were tucked farthest away. Maybe our unknown hero didn't think of it, but someone did, and came up with castling.
Castling serves rook development as well as king's safety, but the latter can hardly have constituted the argument for it, in a Chess game.
We're so used to castling that we tend to forget that it is the weirdest move in Chess, implemented specifically to solve a problem. Chess turned out a great game despite its problem, but it needed an ad hoc fix to do so.
In Grand Chess, pawns retain their usual distance and rooks are free from the onset, so the problem doesn't exist in the first place.

Marshall & Cardinal
Considered conceptually, stripped from its history and and its traditional boardsize, its clear that the Queen constitutes an arbitrary choice that can be avoided by either omitting these 'combinations', as is the case in Dragonfly, or including all three of them.
Capablanca and Lasker promoted the concept of Grand Chess - I'm in good company, thank you - but their implementation was less than fortunate. They either had the pawns on their regular distance and behavior, but then the board would be 8x10, or the board would indeed be 10x10, but then the pawns would be two rows further apart and require rule changes such as the option to move up to three squares initially.
This in turn would raise questions about en passant capture and about pawns moving one square initially - can they still move up to the fifth rank on their second move? In short: problematic.
Meanwhile the rooks were tucked away even farther, so they actually increased the problem they could have gotten rid of so easily.
Capablanca and Lasker were great players, not great inventors.

Renaissance revisited
We live in a time not unlike the renaissance. In those days the printed word accelerated events and led to almost aggressive innovation, now the internet does the same. At the current rate of development, Chess will show serious signs of fatigue within a decade. More study, better programs, more knowledge, less fun, less adventure, more grandmasters, more draws and no more heroes.
I'll allow for one more player to define an era like Fischer or Kasparov.
I don't just see it as desirable for Grand Chess to achieve worldwide recognition, I see it as inevitable as the rise of today's Chess five centuries ago. Programs may be fairly easy to adapt, but will have no opening libraries as yet, and endgame routines are quite different too. Evaluation functions as well as the human level of play still requires some working on, to even become modest. Humans may well have to rely on programs to help map out the opening alleys.

Grand Chess is featured in David Pritchard's The Encyclopedia of Chess Variants (G&P Publications, P.O. Box 20, Godalming, Surrey GU8 4YP, UK - ISBN 0-9524142-0-1), in R. Wayne Schmittberger's New Rules for Classic Games (John Wiley & Sons, Inc. New York - ISBN 0-471-53621-0).

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