I could never wrap my head around why some (or many?) guys get so aroused by watching a blowjob demonstrating the ability to deep-throat.
Could somebody explain please?
The ability to deepthroat is the difference between an okay blowjob and a mind-blowing one. Demonstrating that ability with an object comparable to a penis (e.g., bananas, popsicles, hot dogs, etc.) allows easy communication of that ability, and a rough estimate of whether or not that person could do that to you.