I LOVE yoga any Vinyasa flow sequence that involves this position! I have started taking Ashtanga yoga and miss one-legged dog. In what kind of yoga is this position practiced regularly?
3 leg dog (your arms are legs) is found a lot in Vinyasa flow and Anusara variants of Hatha yoga.If your Ashtanga teacher is not too strict/traditional you could try adding 3 leg dog before stepping forward into warrior 1 in sunsalutation b.