It’s not necessary but it’s the easiest way to stretch the dough evenly.
It kinda depends on the dough though. The place I used to work out, we used a machine to flatten the dough and you COULD toss it, but the dough was kinda stiff. If you tried to stretch it with your hands, it would almost always break. But if you tossed it, that would work.
Where I work now.. .the dough is super soft… I find that tossing it works well, BUT if I toss just SLIGHTLY too high… when I catch it I put a big hole in the dough =/ It stretches by hand much easier than the stiff stuff (OMG LOL STIFF)
As for how well.. well each dough is different, so I can safely say I can do really soft dough and really hard dough well… haven’t tried one in the middle though XD
It’s rare I do anything with pizza dough myself these days (mostly only do it when I do a pizza night at home)
my dough tends to be in the middle when I make it. I toss it a little, but I try to avoid doing it too much. I can be a bit rough sometimes and end up ruining it, lol