Ranked Points Algorithm. What with the Secrets! MMR secret ELO?

I am a player since mid season 3. I didn't start playing ranked till season 5. I know that there use to be an ELO system that was visible of I heard right. Now the system on how to get skill points in ranked games is hidden. I was wondering why this is. I would think that only reason for this is despite this being a team based game if you knew how to earn it would foster individualistic play. This is the only competition I have ever heard of where there were secret stats and you have little to no idea what behavior moves the needle on them. Win and it moves by some number between x and y. Loses and the opposite happens. What are the factors on points X through Y, Riot? This doesn't happen in other sports.

**How would you play if found out that coming to people's rescue gave you more points? What would happen if you knew that taking objectives gave way more skill points than kills? **I dream of a world where you couldn't be trolled out of your own skill points because even though you lost, your mmr (or whatever) continue to rise till you got away from all the bastards. Maybe their needs to be something like Justice Points. They would accumulate through unknown means where as long as you worked hard for the win, you would be put in a special pool of pristine players. What a wonderfullllllll, World.