Engine prelubrication

I recently had an argument with an automotive technician (i am an
automotive service advisor) about engine prelubrication. As i have
thoroughly read Jack Erjavec's excellent book "Automotive Technology, A
System's Approach" i tend to believe that you have to prelubricate a
newly rebuilt engine prior assembling it again. Technicians here have
the opinion that engine prelubrication is not something very important
for the reliability of the rebuilt engine. I would be happy to read
your thoughts on that. Thanks!

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