Coolant in oil

Assuming that one has a problem that allows coolant to get into the oil, is it possible to run the engine long enough to drive all the coolant out of the engine without creating a milkshake and completely destroying the engine?

reason for asking:
Currently tearing down an engine that had what I assumed was coolant getting into the oil.

the oil level went up, and the coolant level went down. After running it for an hour at idle (needed to use the vehicle) there was a lot of vapor coming out of the PCV and breather which I though confirmed my diagnosis. After running the engine for that hour the oil went from 2 quarts too full to 2 quarts low.

video:
83 k20 350 crankcase vapor


when We pulled the engine the radiator was almost completely empty. Only a quart or two came out when we tried to save the coolant.

upon disassembly, the inside is the motor is shockingly clean. The drivers side (PCV) side is squeaky clean with no signs of moisture. The passenger side (breather side) has goopy stuff in the valve cover and sitting on the rockers and head. Definitely moisture related.

the oil was oil when I drained it. Not really happy oil, but not milkshake at all. Some light brown streaks in the pan but not like I would have expected with showing almost 2 quarts over full.

Picture:

how can this even happen? I was expecting a full on milkshake in the oil pan.