Totally agree.
So recently I was playing my smurf account and made it to Platinum 2. My win rate is 24.7% and in my last 10 games, I all made it to Top 4, moreover, 6 out of those 10 games I got 1st place. So in theory, my MMR should be higher than my actual rank. However, the last game I played I got 4th place and I lost 7lp. It's so stupid that I don't even know what to say. Is there any logic behind this freaking system??
And in this situation, I can almost guarantee that if I ever got 8th place I will lose 70+ lp cause that's what happened to my main account and that's also why I don't wanna play my main account.