Just started coming across this in some YouTube videos, supposedly you can use it to “prime” the oil system in a vehicle after an oil change to minimize that fractional moment of a “dry start”. I’ve never prefilled a filter on anything, as a matter of fact, many instructions specifically tell you not to because it’ll allow unfiltered oil to pass through the system. Now, I’ve also never used this “clear flood mode” in anything I’ve serviced, I’ve always just drained the oil, slapped a new filter on, filled it up until it shows right around the top of the fill line, started the vehicle for about 10 seconds, checked the level and added a tad of oil if needed. Anybody ever heard of using this trick?

You're overthinking it.

We used to pull the distributor and install a prime rod connected to the pump key and use a drill to bring up oil pressure without rotating the motor.
Overkill, but it was how we did things on some of our motors.

I figured as much, I’ve always drained, filled, replaced filter and turned key or pushed button.

I use to think it was as easy as drain change filter fill again. Start and check for leaks. Ram says you’re suppose to let the ecodiesel sit for 30 minutes after filling before you start it. And I’ll be damned if you don’t wait it knocks on start up till it builds pressure, very short time. If you wait the 30 min or close no knock. Supposedly is a TSB on it.

It is kind of hard to fill a cartridge filter or a top mounted one.

I did this when I built an engine or bought a crate motor but never did it on oil changes but I am sure it would help reduce wear a bit....

This was fresh rebuilds between runs in race car stuff.

Not on the wife’s car.

x2 Steez when i changed oil on the 430 cid Chevy, in my z/28. Which was quite often. I used that method, May seem like P I A or hassle, but when you have several K's in parts, sweat&blood & costly machine work, not really hassle.
Dang can't believe i sold it.