DAN HENDERSON
PROS:
Dan Henderson is a beast, and a tough son of a bitch. He has underrated timing with his striking. His scrambling on the ground is phenomenal. Not to mention the obvious power in both hands. If he hurts Machida and ends up on top, Machida is in trouble. It'll be hard to sweep him, especially while Hendo is throwing bombs in the process.
CONS:
His cardio and his range will be his weakpoint.
MACHIDA PROS:
Machida has a lot of tools at his disposal with his Karate. If he works his feints early and frustrates Dan, he may be able to catch him with a few critical blows. Those feints will be the key to his striking since Dan will have no choice but to commit with his power strikes, leaving him vulnerable. Dan Henderson does get staggered when he's caught in a feint, and if Machida works his trips in as well, he may be able to score points and tire Dan out for the late TKO in the 2nd or 3rd.
CONS:
If he decides to trade/bang with Dan or get cocky in the grappling he may end up on his back. This will be a nightmare scenario due to Dan's aggressive top-game.