Air Ingress at Oil Change

I’m still thinking about this…. The oil reservoir tank has a dip tube for the oil pump feed line. This assures oil is available for the engine even if oil level in the tank is low. When you drain the tank, this dip tube also drains and looses it charge of stored oil. When the tank is refilled with fresh oil the dip tube remains empty. What this means is a slug of air approx 8” long travels into the engine oil galleries (hydraulic lifters). Looks like everyone shares this problem during oil changes unless a complete air purge is done. Maybe fear of air-entrapment in the hydraulic lifts is a little over-played….