Atd translation: balloonheaded clarity

[Mike Jing]

P176.10-18   The altitude, the scale of the country out here, put a
balloonheaded clarity onto vision when directed at mine owners and workers
alike, revealing the Plutonic powers as they daily sent their legions of
gnomes underground to hollow out as much of that broken domain as they
could before the over-burden collapsed, often as not on top of their heads,
though what did it matter to the Powers, who always had more dwarves
waiting, even eagerly, to be sent below. Scabs and Union men, Union and
scabs, round and round, changing sides, changing back again, sure didn’t
help with what he felt no embarrassment in thinking of as a contest for his
soul.

Why is this clarity "balloonheaded"? Is this good or bad?