Not to belittle him but my grandpappy said his jokes were written by others and he read them off cue cards. He still was a great guy accordingly.
....he had great timing, and could ad lib at the drop of a hat
“You can pull my left leg, and you can pull my right leg, but don’t mess with Mr. Inbetween.”
All of the great comics who came out of radio had writers. The demands of a weekly show, plus club appearances (and later TV) made it impossible for any comedian to write all of his material.
If anyone doubts Mr. Hope’s comic skills, check out his Tonight Show appearances in the 70s and 80s. At an age when most comedians were retired or dead, “Rapid Robert” was very fast—and very funny.