Err ... the link given doesnt mention saberstaffs at all.
So you dont need a saberstaff to get Cleave.
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And no, the saberstaff doesnt make much sense in reallife. It certainly doesnt give you an advantage in fighting crowds.
You can see it in the movie, too. When Darth Maul fights Qui-Gon Jinn and Obi-Wan Kenobi, they never attack him both at the same time independently.
If he wielded two onehanded weapons he could defend against that. With the limitations of a staff, he cant. In fact since he cannot touch the staff anywhere except in the middle, his possible moves are very constricted, compared to reallife staff fighting where you of course often hold the staff near the end to get range.
They got a pro fighter to play Darth Maul so it wouldnt look so bad, but even that guy could only do so much.
Of course thanks to Disney, this is by far not the most poor lightsaber design in Star Wars now.
But they did ONE good thing and thats introducing a lightsaber with a guard. Thats a huge advantage. Which is why many reallife swords have a guard.
They also sometimes show force field shields in Star Wars, who solve two of the main problems a reallife shield has - you cannot see whats happening on the other side, so you're blocking your own view, and reallife shields cannot be too big because then they are simply too heavy. Well, a force field has no weight at all.
So far no Jedi is ever seen using such a shield, though.
What WOULD give an advantage fighting crowds would be a twohanded lightsaber. Greatswords offer enormous reach and thus allow to defend against multiple attackers in reallife. A lightsaber version of that would make a lot of sense.