Can a staff member please explain the Arena Rules

I'd love for a member of staff to thoroughly explain the arena rules, and tell me exactly what are the rules for receiving rewards for the end of the season.
Almost every season excepting one I've competed in, I've had my team deleted when top 3 on the ladder in 2s or 3s. The first time, it was because I had dropped below 1.5 mmr to around 1450, I was new to the server at the time and it does not state anywhere on the forums that this was a rule, so I let it pass and tried the next season. I tried a few seasons later, and I had my team deleted in both 2s and 3s deleted. In 2s it was deleted because I had dropped MMR earlier in the season, I'd like to emphasis that this was done with different partners and we dropped MMR in different teams as what's the point in playing at 2.5k mmr in a 0 rated team? This new rule which Warmane decided to not tell anyone about resulted in literally almost the entire top 10 being deleted because this had never been a rule before, and as I previously stated, was never a rule until now. I played 3s that season as well upto top 3, where I then had my team deleted for some unknown reason. The team deletion was after the other teams who "had broke the rules" were already deleted, so the only reason I could think as to why our team was deleted, was because we played with another player who was about 300 less MMR than us for the last day of the season, but still got the same exact queues vs the exact same players. We played with this other player because ours was unable to play that day.

It feels like these "rules" are based on the number of reports someone has made on that specific team, for example, I saw a warrior/hpal team who got their rewards in 2s, whilst the paladin played with a number of different players during that season in that team. I also saw a 3s team who got their rewards when they played with numerous other players with lower mmr. Why was their team not deleted as well? One rule for one team, and one rule for another.

The main reason I've made this post is because I want to ask what the exact arena rules are, so people can actually see without constantly second guessing themselves. In the post http://forum.warmane.com/showthread.php?t=382540 the rules for qualifying for the rewards are stated:

Players will not be eligible for rewards IF (team itself will remain intact as part of a rank slot)

Personal rating is not within 150 of the Team Rating.
You do not have at least 70% of the team's games played.

MMR Dropping:

We also have some new rules in regards to MMR dropping on realms where it is applicable:
Bans for extreme cases.
Removal of the team from the ladder and disbanding of the aforementioned team, thus meaning disqualification of receiving any seasonal rewards.

There is no mention on either of these quotes that states whether you are or not allowed to play with other team members who could have a small amount of difference in terms of MMR to that of yourself or other teammate. I've asked the head gm Aldatharios a number of times and been outright ignored when questioning about my team deletion. I'm asking this now because I'm unsure as to whether or not to even bother playing 3s because one of the players I was previously playing with has lost the account, so are we supposed to just remake the team at 2.1k MMR, when it's bad enough already trying to get queues at 1.5k. There is also no actual confirmation on whether ot not it's even disbannable to drop MMR to play with a new partner now, the rule is no where to be seen on the forums.

Btw, all I've spoke about here is on the Icecrown server, would love a reply from a member of staff to confirm some of the questions I have in the post. Sorry it's a little ranty, it's just a very confusing system.