The bolded part was my statement that en passant doesn’t change the game much. You say this is a “Hidden flaw” in my argument, but your counterargument doesn’t argue that it does.
In fact, your entire post is a straw man. Who said pawns were a tiresome inconvenience? Are you sure you replied to the right post?
I mean, I’m not mounting some huge campaign to have en passant removed from chess; I just don’t think the rule really serves a purpose.
I bought a set made out of chocolate once. 
And they’re still making them!
I love Kriegspiel. The trick is finding two people round here willing to play it!
You can only move pieces with your right hand, as your left hand has a SockEm-Bopper on it. You have only 60 seconds between moves. You may only punch at your opponent on their turn, but you can try to block their blows. Also, you may not upset any of the pieces on the board or you automatically lose.
There are plenty of lines of play where the threat of en passant capture is highly significant. For instance, in some lines where White is attacking Black’s castled King with an attack directed against h7, he may be able to drive the Knight from f6 by playing e5, also opening the diagonal to h7. In that position it’s very much to the point that Black can’t simply scupper the attack by playing …f5, closing the diagonal again, as White can play e5xf6e.p.
I don’t know about a straw man, but I was trying to establish what “pawn-heavy strategy” means - if it doesn’t mean that pawns are a tiresome inconvenience, then by all means say so and say what it does mean.
Can anyone explain to me the idea behind the “no castling out of check” rule. I understand “through” and “into” (duh) but with the God save the King mentality that abounds in chess, “out of” seems that it should be permissable. Would modifying this significantly alter strategy?
Early versions of chess had no castling. There was then some dalliance with a ‘King leap’, but eventually castling came in during the 15th century.
I can only speak as an experienced player why all this happened. If the King is stuck near its original square, then best strategy is to attack it. This is great fun, but means positional chess and most endgame play is ignored.
Castling allows escape from a central buildup, and also brings a rook into the game.
Now there should be a ‘reward’ for attacking the King before it can castle (or perhaps a ‘penalty’ for leaving your King ‘unsafe’), so the rules don’t allow a player to castle once the King has moved (or with a particular rook if that has moved).
As you say, you can’t castle through check or into it. But being checked meaning you can’t ever castle seems too strong, so the balance is that you must first get out of check without moving your King and can then castle.
