@Riot: Is there extra LP loss for playing solo cause of the premade MMR algorithms?

Ok, so you know that premades get matched with people above their MMR. Which means if you join ranked solo, you will constantly see a group of people a few divisions below you. Which means the actual MMR average for the game is going to naturally be below your own MMR.

Now LP gains and losses are based on your rank's average MMR compared to the average MMR of the match. If the MMR of the match is lower than your rank, you will gain little for wins and lose a lot for losses. If the match MMR is higher than your rank, you gain a lot for wins and lose less for losses.

I'm definitely losing more LP for losses and gaining less for wins right now. It's possible that my MMR is lower than my rank, but I really don't think that's the case right now. So I'm incredibly suspicious of the way I'm being matched with premades that are a short deal behind me. It really feels like the matchmaking system is punishing me by putting me into lower MMR matches cause I'm a solo player.

Can anybody from Riot confirm that when it comes to LP loss/gain, whether or not the system measures the MMR of the game based on the average of every player or the MMR used for matchmaking which boost the MMR of premades?