Yes, I've heard of this before. I think it was mentioned somewhere in the audio commentary, but I'm not sure. The directors wanted Scar to die in the flames at first because he would have been surrounded by the flames. And by throwing Simba over the cliff, he accidentally would have saved his life.
But I'm glad they changed that idea to the ending we have now.
A agree with the people from TVtropes. Simba has to be the hero so that Scar is brought to justice.
For me, there's no other way how things should have been