How did the factory break in cams?

ir3333 said
in was through the Oshawa plant back in the 60's.Every car was test run on rollers
as part of the production process...at least that's what they showed us.
..on a side note i don't think you vary rpm during cam break in..steady 2500 rpm 15 min.

Comp Cams recommends 2000 rpm with occasional blurps to 2500 rpm for 30 min. with the one I just broke in.