Everyone gets caught on the pet tanking when it comes to beast master but if the pet is a part of you (as in the weapon, no more than buttons and commands) then technically it is still a beast master with no delay or lag like in Summoners/Scholar pets. Least that is how I see getting around the whole deal or worry, the new weapons simply being a new pet or the chain/link that binds you to the pet. Like stance wise when the weapon is out the pet is in front and on guard/ready where as put away he/she walks by your side like a loyal pet.