Is Op.GG mmr reliable?

http://na.op.gg/summoner/userName=Dakkimchi I had a huge loss streak and demoted to gold, but then I got lucky and then climbed back in 6 games. I knew my mmr was still shit, so I tried to win as much as I could. Now, I'm at Plat 5 58 lp with 1798 mmr (and the average for this is 1755). Am I technically still low mmr because there are a lot of low mmr plat 5 people, which brings the average down? I'm still gaining 14 lp a win (I lost one game, which led me to lose 21 or 22 lp).