I believe solely in running it like hell to break it in, now it might not apply to 2 strokes so well, but 4 strokes definitely. Running it hard and hot gets the lube in all the right places (it is designed to do just that, more oil be with more rpms, add that mystery oil additive to make sure it just gets everywhere) and also gets the rings seated nicely (its forced air cooled, don't worry about overheating a 4 stroke with forced air except for special circumstances) by running it hard to get them driven in well, you only get one chance to do this, and if you plan on using it hard then seat the rings where they will be used, not almost used.
The engine is a pretty formidable foe to taking on ideal characteristics when you talk 4 stroke vs 2, the 2 stroke is firing twice as often with generally more energy in a smaller box, with less moving parts and to top it off it burns it's oil instead of using it from a set supply of oil that increases it's spread with engine speed, the 2 stroke will use the same relative amount each time in the combustion chamber which changes how much is being applied to the cylinder relative to heat build up, 4's just keep spitting oil in there and if it's running faster just means less has left the area it's needed, and the design pretty much ensures it gets the oil it needs regardless of rpms (up to a point of course)
I might not tear into the 4 stroke ever, BUT I have broken them in, and maintained them with very astounding results by my calculations (I wouldn't be proud if I was killing my engines faster, I'd be worried and looking for professional help) and wound up having 4 strokes that not only have better gas usage but also have continuously comparable power in comparison to others who's power seems to continually diminish year after year.
I find a few sites while trying to back up my learnings, but this one is by far the best,
http://www.mototuneusa.com/break_in_secrets.htm I don't ever open my own engines but the mechanics also don't think the odometer/hour readings match the motor either, so I'll call it a fair bet I'm doing it right.