IF the enemy team remakes you should get lp

Because with logic you can defeat any statement.

IE) What if players learned a way to go into flex games and constantly dodge/remake. They could easily win trade, with one team getting LP and one team not and staying the same. Soon you could easily have team boosting.

People will use and abuse your idea, unless there was a way to protect it. However, coming up with a way to protect it causes even more problems and issues to fix. So its just simpler to keep it as is.