I'm beginning to train one of my GSDs to come to me at a distance and immediately take up a sitting position between my legs with his back to me. I simply recall him with "come" and when he's near me I say "achtung" and he takes up the position. Luring him into this at the beginning with food was incredibly easy as the last part of the drill is old hat, the drill ends in a sit, and it is much easier to present the treat to him with his back to me.

I'm doing this because, should I ever need to, if the dog is off leash, like in the house, I can immediately squat and wrap my arms around him and he is facing whatever I am facing.

As he comes to me and hears "achtung" he runs past my left leg, and does a 180 left turn to be between my legs. The only other way I see it is for him to run between my legs and do a 180 behind me, which seems to have some inherent problems, one of them being that a "left pass" requires one less step than a through the legs approach and the through the legs approach creates a great chance for handler crotch injury.

Once he gets used to this I want to work on walking forward and backward with him between my legs. This seems like a really useful combination of obedience and a very intelligent starting point should the dog need to be sent against a decoy who is only a step or two away.

Does anyone have any sugguestions/tips or know if this a part of certain training disciplines or trials? Any basic or advanced info. on top of what I've written would be great.

Not really knowledgeable in this field, but I saw a piece on something like this on the K9 to 5 show on Animal Planet. They did a story on the police dogs that the French use to patrol the Louvre. The dogs are trained to walk between the suspects legs (rather than the handler's legs) just like you describe. Might be worth looking into.