From your article:
1) If you have shavings and pieces in your rebuild, you've done something terribly wrong. 2) Encouraging those pieces to move through an engine is the last thing you'd want. If you've got something hung up you want it to stay there, not move into a tighter place a score the inside of your engine even worse.
Not that I've ever heard of as a common practice. The parts are heat treated as they're built, but are assembled on a line piece by piece and dropped into the vehicle. They don't put it all together and then heat treat it.
The main reason is that race engines (true high performance engines) have life expectancies in hours. Those engines perform at peak for the duration of their life so they don't want to waste time doing things that don't contribute to performance, but are ultimately detrimental to it.
As I said, breaking in engines went away a long time ago and lives on as "accepted wisdom". The next time you rebuild an engine, put it back together, idle it long enough to bleed the coolant and check for leaks. Then close the hood and drive as normal.