I followed a strict breakin regiment for.. oh ... about 1 day. Now I'm solidly in shumby and Musashi's camp. Drive it like you stole it.
With the ultra elaborate breakin schemes here, it almost sounds as if there's some masochistic pleasure obtained through extreme restraint. Do your balls turn blue while driving?
The percieved benefits (i.e. LOT of mild-moderate acceleration and engine braking to get good seals. Orly?) are screaming placebo.
Seriously, as long as the engine is at operating temp, I'll do whatever I please to it, and that usually includes RPMs well beyond 4k.