Since he is the camp's intelligence officer, he is not on combat duty and can therefore maintain his gleeful attitude to the men risking their lives in the air.
He explained that there's simply nothing else like it, nothing else that has the same bravado, the same swagger, the same gleeful self-aggrandizement and sense of camp.
He speaks in a distinctive squawking voice, produced by a contrivance known as a "swazzle" or "swatchel" which the professor holds in his mouth, transmitting his gleeful cackle.
Sometimes each subsequent verse and chorus is a little faster and louder, with the ultimate aim of making people chaotically run into each other in gleeful abandon.