A term coined by Jared A. Sorensen in September 2001 for the idea that GNS Simulationism doesn't really exist as its own agenda, but rather is a neutral state in-between Gamism and Narrativism (and originally that this state represented a retreat from the other two modes). i.e. G and N were the ends of the horseshoe, while S is the middle. This was adapted later to the idea of a plane which was G vs N on one axis, while the other is low to high Fidelity. i.e.

(Note: it's called the Beeg Horseshoe Theory because like a horseshoe, the two sides curve around so that they almost meet. This is to reflect the similarities between the two styles of play. At their extremes, it also puts them far away from the middle of the horseshoe. - JAS)

What was seen as GNS Simulationism is in this model high-Fidelity forms of Gamism and Narrativism.

References:

• All-out dissection (LONG AND BRUTAL) (The Forge, Apr 2001)
• The Beeg Horseshoe Theory (The Forge, Sep 2001)
• Beeg Horseshoe Theory Revisited (The Forge, May 2003)
• The Roots of Sim II (The Forge, Feb 2004)