At low elo, you either CAN split push, or you CAN'T. I'm not saying like you physically can't do it... I'm saying you will get teams that don't understand the concept of split-pushing, and they will just yell at you for not grouping up.
Typically they will hard engage in a 4v5, get destroyed, and then immediately look around the map for anyone who wasn't in the fight. You are off far away pushing a lane, so they just blame you for their bad play. "if you were with the team we could have won that fight"
It just gets worse from there. Seriously... it's pretty annoying when someone dies and the first thing they do is look for someone else to blame. It's obvious to everyone on the team that the person is just making excuses.
You'll either get the team that hard engages every time you leave to split push, or you get the team who retreats and/or doesn't put ANY pressure on another lane... which lets the enemy team send a couple people to your lane to destroy you. If you die... get ready for the team chat hate to roll in. "omg noob this is why you shouldn't be split pushing" or "just stick with the team and stop feeding" etc.
In those games just consider the game lost... because you aren't going to win in a 5v5 anyway if your four teammates are getting wiped in team fights without getting a single enemy kill. I mean really what good would you be in the team fights? Maybe you get 2 or even 3 kills, but their team gets an ace and takes free objectives.
So split pushing is only really effective when the remaining 4 people on your team can actually hold up for 30 seconds and keep the enemy distracted. At that point, the enemy has to make the choice to just fight it out with your team, or send 2 people to your lane to stop your split push. If they fight it out with your team, you get a free tower/objective. If they come up to you, you make it 4v3 in your team's lane and you can potentially keep 2 of the enemies busy chasing you for a while.
It can be SUPER effective if pulled off correctly. Like it wins games and you barely have to get your hands dirty. Also you have the added bonus that if the enemy team pushes out a bit and your team hard engages them and drives them back, you are probably "behind" the enemy team (pushed far up in one of their lanes) so you can successfully come in behind them and cut off their escape path for some easy cleanup kills. :)