Reworking the 273 Adjustable Rockers

Correct on the fist part. but the oil is for the pushrod tip and not to adjust anything.

The oil in the lifter is doing the adjusting, once the rocker is adjusted, that has nothing to do with oiling the valve and pushrod tips.
I meant the hole was drilled to keep the adjuster from turning. I have noticed when screwing in the adjuster, it got harder to turn when it went past that hole. Did not think oil would come out of there.