Chris I'm glad you asked the above,
I'm 49 years old, and all my life my dad has been telling me to exersize a fresh engine in the manner I've listed above. I really thought it was back yard talk, as my dad is 72 years old and can't read or write. I then noticed in the owners manual for the Viper it said, during breakin, do not run the car at a sustained,'steady' rpm, meaning don't get in the car and get on the freway for a long trip without varying the engine speed. So my dad was right. My dad would say you will permanantly shortan the life and lower the horspower if you don't do this,but you know how listening to dad can be sometimes. I wish the factory would make this clear. I spoke to my uncle that can read and write, and has been building engines that cost up to $50,000 for the last 40 years, this question. All he had to say is that you have very little time to break in an engine properly. Ring technolagy has improved greatly over the last 25 years, but it's far from perfect. It doesn't matter who made the engine. It really something to watch this take place on the dyno, but they really try getting done quickly, as to not let the oval shaped pattern in the cylinder walls get started. They run all engines up to 80& of their max, then after about 15 pulls they move up to 90% or better, then right at 90% of there max rpm.
Here's a very interesting story that happend to my uncle about 15 or so years ago, he really learned a lesson the hard way. He built a circle track engine for a customer,'about an $8,000 engine, and the customer insisted he put systhetic oil in from the start. When they dynoed the engine, they were unable to seat the rings, loosing about 20-25 horse power from where this engine should have been, he looked further and noticed the high levels of hydrocarbons, 'I think that's what it was'. They drained the oil, and still couldn't get it to seat, as the synthetic oil had penetrated the pores of the metal. They can't sit there all day on the dyno trying to seat this engine and the customer sure can't do it on the track. They had to completly rebuild the engine and cook the block to high temp to remove all traces of this. Now on the street this breakin would have eventually happend, when draining out the syn. Mack truck engines forbid the use of it in a new engine, but welcome it after seating has occured. I went through what my uncle did, with a new Mack truck. One gallon per week slipping past the rings until I drained the Amsoil syn. out of it. It then took only two weeks of daily use for it to stop oil consumption completly.
Your question about how this affects emmisions, well synthetic oil has a slightly higher flash point and hydrocarbon levels are allways lower when using it. Sadly what ever the emmission level is with synthetic in a brand new engine, it will never get better, as it would with petro.
True breakin procedures are somewhat complex. The factory really does want you to do this. They just don't want you bouncing off the red line all week long in your new Viper. I'm sure when they say 4-K max for 1000 miles, they know you'll be doing a bit over that anyway. Kind of like the posted speed limit.
Exercising the engine will push the rings in a perfect cirlce, cruising will forever halt this, as will using synthetic oil.
I hope I've made things a bit more clear for you on this.
Skip White