hereorthere – please don’t put words into my mouth; since there is lots of back-up that CS is ok so I, as “in my opinion”, have a s’vara whereby hashgacha on milk attests that it is kosher as does a Jew who claims that he saw all the cows being milked.
Many restaurants and most retail kosher products; the hashgacha is on a “yotze v’nichnas” basis. The mashgiach pops in unannounced from time to time. This is what Rav Gornish does as well.