Short runs start light and increase the load as time goes by..
After a couple of short runs/heat cycles check torque and look for leaks, check lash.
After a few times things will settle down and you can start racing it.
Change the oil after the first and second run.
Thats when the engine will shed the most material in break in.
Use something like Rotella T for break in ( lots of detergents to deal with the by products of break in ).
Cheap, save your fancy oil for race day ( or what ever you use ).
How well an engine breaks in has a lot to do with the quality of the bore and hone job.
Better they bore finish, and grinding machining of parts the faster and easier it will break in.
Better the machining the closer your tolerances and the shorter your break in.
Think about it break in is wear and wear is your tolerances changing.
Run hard out of the gate. You want to wear in the rings while the hone markings are still in the walls. If you baby it you wear some the hone Mark's and dont wear in the rings. If you dont wear in the rings you dont get as good of a seal.