What if Isengard joined forces with Gondor?

[mhagain]

Saruman and Gandalf combined would have been nearer a match for Sauron without the Ring, but they would still have been under the prohibition against taking direct action in the War, and so would only have been in a position to give advice.

The point about Gollum is a good one. Frodo would never have been able to destroy the Ring on his own, and it was only through Gollum's intervention that it was eventually destroyed. I don't believe that anyone else would have been able to intervene in this manner.

The story as I see it evolving is:

• With the combined advice of Saruman and Gandalf, and with an undiminished and undistracted Rohan available, the good guys can hold out against Sauron for longer, but they don't have sufficient strength to be able to ultimately overcome him.
• Frodo and Sam make it to the Crack in much the same way as before, but without Gollum.
• Frodo claims the Ring.
• With no Gollum to intervene, Sauron eventually gets it back off him.
• Much badness ensues.