Everest News, an organization that relies heavily on actual climbers in the Himalayas, and is used by same, presents a well-constructed theory (with pictures) on why they believe George Mallory DID make it to the top of Mt Everest in 1924.
It's a long article, but the more you read, the more fascinating it becomes.
On a side note, when Mallory's body was discovered in 1999, I wrote this as a sort of tribute:
Blood and Stone
He awoke from a wretched dream about sliding and falling among rocks.
Gasping like a fish thrown from a bowl, he stubbornly tried to lift himself upon his elbows. A sharp pain forced him back down on his face.
My leg's broken, he thought. I can feel it. He drew a sharp breath and felt something grind in his chest.
Even at this altitude, my ribs shouldn't hurt this much. A sad calm washed through him like a slow wave rolling along a beach. The blood from his wounds was already soaking through his clothing in several places. Within seconds, the blood simply froze and clotted. The bleeding stopped.
Whiteout had cut visibility to a few miserable meters, yet the wind still screamed across the cold stone and frozen snow as if the mountain were angry.
He smiled through the pain. Yes, go ahead and howl. You have good reason. I beat you.
He wanted one last look at the summit. However, the mountain had surrendered enough of its soul on this day. Heavy cloud now blanketed the top. A final glance was denied. He raised his head a few inches and took a deep breath.
There was no reply.
Reaching back over his shoulder with his one working arm, he felt around a bit. The bulky oxygen tanks and his rucksack were both gone. He suddenly realized how foolish it had been to store the camera in the rucksack.
Maybe someone will find it. Someday. Then they'll know.
George Mallory took a last gasp and died.