In a former life I was on an engine R&D team. We developed engines, did destruct tests, wear tests, established oil parameters, and optimal break in procedures. There is no way in HELL we would "mototune" an engine that we expected to last several thousands of hours.
Accelerated hard break in procedures have been developed for race engines that only need to last a season, or in some cases, one race before they are rebuilt. Normal break in procedures take too long for frequently rebuilt engines.
Problem with railing on the engine too early in the process is that one of the critical elements of engine break in, work hardening, has not occurred yet and clearances can be lost prematurely, and uneven wear patterns can develop on soft metal surfaces. You -can- apply these methods to an engine and it -might- go 200,000 miles but it's a crapshoot. You're just as likely to start blowing smoke out the tail at 2,000 miles.