I think the last 3 wins 'only' moved me about 10.000 positions.
As discussed elsewhere, there seems to be a problem with the way automatcher uses the rating, though. Even in my 'stabilized' category, I still draw teammates with next to no xp. I suppose they just got the game recently and that you don't start over on xp if you rename your account?
the upper you go on the ranking and the less positions you will climb per win obviously (think of ELO distribution between players like a gaussian distribution (bell curve)).
In team games your teammates aren't necessarily of your same ELO rating, they could have any. The team gets an overall ELO that's the average of the players', then the automatch looks for a team with a similar average ELO