The "taco" hold is a useful shooting position - but only with a light-recoil round - or, a VERY effective muzzle brake. To simply describe it - you basically hold the gun close to the body, with the non-gripping hand grasping the gun or scope with an overhand grip - hence, the "taco" reference. Since this is a standing-only stance in silhouette, could easily translate to field shooting. Personally, I will utilize a support whenever possible !