Comments/Ratings for a Single Item

There seems to be a missed hole in the rules.  If I follow your rules
exactly and interpret 'how I see fit' (which may or may not be correct
in the spirit of the game, but that should be addressed in the rules).

In your sample game at move 12. Bb5/c6/d7+, you have a lost queen because
the king is in check and the queen is under attack by the knight. with the
reply 12... Ke8:d7.  But in strict adherence to the rules, would the
following be a valid response? 12... Qh2/h4/g4/d7/f7/g7/h7/e4+  This gets
the queen away from the knight, removes check from the bishop, and
doesn't check the white king until after the black king has been removed
from check.  There were no new checks encountered during the swaps (with
rule 2.4, something that a move like 12... Qh2/e5/c5/c6/d7/c8 does not
hold to, as the c5 swap puts black illegally in check by the white queen),
and the end of the board position ended with black not in check any more. 
In general, it seems that this variant makes the queen far too powerful
and hard to capture, as it is able to move itself out of harm's way with
relative ease.

If the following rule is added, it should make the rules less ambiguous
while maintaining (what I believe) is the original 'spirit' of the
game:
8. A player must not have his own king in check at any point along a
series of swaps, even if the final move position leaves his king not in
check.

Your rule seems appropriate. These original rules create too much havoc on
the position, and make medium-term strategies difficult to plan. 

At that time, I start playing a better variant of the same idea: Balanced
Swap Chess (http://www.chessvariants.org/diffmove.dir/balancedswap.html).
In this variant, the moving ability is much more constrained: only one
swap per move. 

Thanks for your comments! If you like to try a game of balanced swap
chess, email me.

>did you consider the basic one-step swap which I described in Switching
>Chess? 

To be honest, I don't remember :-) But I guess not, usually I tend to
create faster games that FIDE chess, and by allowing just one move per
turn (which might be a swap) my intuition tells me that it would be harder
to mate a swapping king (of course, I may be wrong). Anyway, I don't
recall ever tried the rules of Switching Chess on my chess ruminations.

>I described Switching Chess before I knew of Swap Chess or Balanced Swap

>Chess, however, I later found an applet by Ed Friedlander called Swap
>Chess 1 that is almost identical to Switching Chess and predated it, 
>yet it is not attributed to you. 

I suppose Ed Friedlander read about swap chess here at chessvariants.org.
He has applets of other games of mine (like magnetic or capture-the-flag
chess). I think that applet implements Balanced Swap Chess.

>I guess I am not sure about the originality of Switching Chess vis-a-vis
>Swap Chess.

This seems a case of convergent invention. The idea is too simple and will
probably be 'found' many other times. Eventually, it was already invented
before 1998.

Cheers,

Swap Chess allows serial swapping as a move along subsequent lines of attack.  Swap Chess has never been put up in Game Courier like Switching Chess.