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Hence the reason outfielders all seem to do better than they should here - because the ball DOES hang up and it can't get through the marine layer for several months of the year. The outfield isn't especially huge, it's just larger than can be overcome by most hitters in cool months thanks to the conditions.
Which means a home run hitter like Cruz who can defeat it in all months is important. We can play the speed-and-defense game; I'm not opposed to that. But Safeco suppresses things other than homers, too, so those defensive speedsters had better sting the ball when they make contact.