There are a bunch of reasons why the small builders don't run break-in schedules.

They do not have dynos capable of running break-in schedules.

They do not have the manpower to run a dyno for hours and hours for just one engine.

They don't have enough dynos to run multiple engines on break-in schedules simultaneously.

They don't have customers who would would be willing to pay for hours and hours of break-in dyno time.

Their horsepower tests are run on the fly, and over in a matter of seconds, compared to the person who leaves the engine at full throttle across the lake (or other body of water).

Hope this helps.

Michael