It was in a british mag, superbike i think, late last year. They did a comparison when running bikes in, using a GSXR750, again, i think.
Can't remember EXACT figures off the top of my head, but general gist was that thrashing from new (0 miles!) gained a GOOD horsepower increase by as little as 1000 miles over the same bike run in to manufactures guidelines.
The thrashed bike gave something like 3-6 bhp MORE and generally felt much more responsive to use. The normally run in bike felt tighter and slower BUT much more refined.
After stripping both bikes down at 10,000 miles thrashed bike showed slight signs of wear but nothing TOO serious but they did say that it was sounding rougher even though it ran just fine still. Properly run in bike when stripped down was perfect.
They came to the conclusion that the BEST way to run a bike in was to follow manufacturers guidelines till FIRST scheduled oil change then it was good to go! Use and thrash as required!
Being TOO gentle when running in can actually have an adverse effect on the metals in the bores, allowing them and the pistons to glaze over, losing power. They need to go through heating and cooling proccesses to properly harden (not the 'scientific' word, can't remember what it is!).
If you buy new bikes and only keep them for less than 5000 miles or so, THRASH THE TITS OFF IT and let some poor other sod deal with the future repair bills! :rant
If you keep bikes longer, like i do, DON'T! :rotfl
All the above is from my memory so i can't be held to exact figures or consequences....:devious
p.s. I LOVE my bike so would personally follow manufacturers guides to first oil change then open her up fully, but in stages, to 1000 miles, then it's good to go!