With as much as I hold him and carry him around, he has not pooped on me! Not ONCE!! Weird I know.
Chickens in general seem much less likely to poop while being held, and more likely to poop when they're just sitting or standing somewhere. (Sitting or standing on a person's lap is not "held" for this purpose.)
It's not 100% reliable for most chickens, just a general observation that does seem to line up with what you noticed.