I wonder about that tiny oil hole. I may be over-thinking it but you'd probably want to keep the oil thinner and cleaner to keep from blocking that passage.
I was concerned about the holes getting plugged, but have had them for 7 years. Have had them out of the motor about 3-4 times since. Check each one and they were clear. I don’t remember who made them, but I would go EDM again in the future.
