Greetings,
While I am usually all for easier paths to allow other players to obtain achievements. I feel that the Training Grounds should not count towards the Battlemaster Meta Achievements from the standard battlegrounds for a variety of reasons. The primary reason being that it encourages a large number of players to enter training grounds intentionally looking to throw to allow easier achievements. This at a time others are using Training Grounds as intended to learn new specs, learn how to do battlegrounds, or farm Wins Achievement. Its counter intuitive to allow progress on Metas.
It encourages Gameplay Sabotage to allow players to earn achievements such as “Defend 50 Times”. My concern is players are abusing and detracting from the play of other players to do so. An excellent example was my last Arathi Basin Games where I had a priest pulling people away from flag to allow enemy team to cap or allow their friend to cap. Or, druids in stealth watching flag be taken so they could cyclone and defend. This is not in the spirit of game, and feel the only way to counter this type of behavior is eliminate the ability to earn these achievements.
Just my personal opinion as someone who understands both views. If its intended to learn then you should not be earning honor or achievements, and if its intended to be competitive than it should follow same rules as other PvP that disallows Gameplay Sabotage. IMO