if you have a very high mmr and just have created your team you will notice you win "96" rating as you say, until you start losing and you eventually end up at your peak and start win less and less as your win % start to go down and you end up where you should be for the moment in rating.
If you create a new team, you will gain 96 rating per win until your team rating gets close to your MMR. Once you've gotten close to your MMR, you will gain fewer points.
In order to get to a higher team rating, you will need to improve your MMR. You can do this by chaining together wins against opponents, particularly those who have a higher MMR than you do. If you lose to someone with a lower MMR, then it will take much longer to raise your own MMR. Consistency is the key.
The system tries to match your team rating with your MMR, so the further away your team rating is from your MMR the more points you will gain/lose with each win/loss. I believe the cap is 96 points per match.
The ratings displayed at the end of each match reflect each players' MMR, not their actual team rating.
The points gained/lost displayed at the end of each match reflect each players' team rating, not their MMR.
Although this sounds logical I still have doubts. For example, sometimes I run on same opponents for 3-4 matches in a row. We both make 2 wins each and still they receive that magical 96 points. Shouldn't they receive less since they lost previous match to me?
Because they have low team rating. The rating change you see in the endscreen of an arenagame is the team rating. If they had 1600 mmr, but 1300 rating, they'd gain somewhere around 50 rating (wild guess), but if they were on 0 rating with 1600 mmr, they'd gain 96.
The closer your team rating gets to your mmr, the less you gain. If your team rating is higher than the mmr, you'll lose more than you gain. Say you're 1500 rated on 1300 mmr, you'll gain like 6 for a win, but you'll lose more like 20.
Basically the mmr tries to get your team rating as close to the mmr as possible, if that helps at all.