HEAD can be such an intensly intimate experience between men when there's genuine chemistry between them. This is most often 'achieved' and guided by an experienced TOP and dedicated cocksucker, novices and experts alike.
The best cocksuckers rely on cues, subtle and/or explicit, from their TOPS. Their every action is a reaction easily observed in his TOP's body-language, breathing and presence of mind.
Of course, oral skills are essential, but I'd argue that 'intuition' matters most. For me, it's in his eyes, focus and willingness... to put my cock and my needs front and center. His needs are met inherently by the pride gained in meeting mine... and so it is.
To illustrate my point, take a look at this TIM clip,
featuring Dan Fisk's cock
being properly worshiped, sucked and serviced
through a glory hole by a very skilled cocksucker.