Mustafar Vader vs. General Grievous - h2h

Who wins?

Let's make this simple shall we.

But Obi-Wan's arm had the Force to give it strength, and the general's arm only had the innate crystalline intermolecular structure of duranium alloy.

Grievous' forearm bent like a cheap spoon.
......

Anakin roared and flew at him, using both the Force and his body to crash Obi-Wan back into the wall once more. His hands seized Obi-Wan's wrists with impossible strength, forcing his arms wide.

"I am so sick of your lectures!" Dark power bore down with his grip. Obi-Wan felt the bones of his forearms bending, beginning to feather toward the greenstick fractures that would come before the final breaks.

- RotS Novel

Anakin is stronger and faster + having learned tier 9 fighting skills.

He wins

Not faster

Grievous wins.

Vader handly.

Why do people think Vader wins this?

Kenobi trades h2h blows with Anakin, neither is clearly superior to the other in that area. Kenobi goes h2h with Grievous and gets thoroughly manhandled even when in possession of a melee weapon. I think the victor here is obvious.

Man I love Grievous but he just simply can’t win this

Grievous shreds.