The BMW 1100RT break-in guidelines -- or "wearing-in" as he puts it -- are excellent. But I think even the most diligent owner would only follow them for the first 600 miles, and would tire of driving like that afterward. However, most of the benefits would already be attained in the first 600 miles.
It has also been noted that BMW no longer uses a special light-weight "wearing-in" oil. So apparently the BMW engineers decided it is better to slow the wearing-in of some parts, rather than accelerate the wearing-in of others.
I do not know how to compare an 1100 cc 2-cylinder normally-aspirated gasoline engine, with a 1900 cc 4-cylinder turbo-diesel engine. An oil-cooled BMW boxer engine can easily run for 100k miles (or more) if properly cared for, the TDI engine 300k-400k miles (or more).
Drivbiwire wrote: "First 1,000 miles
Keep rpms below 3,800. Avoid steady rpms. Frequent firm application of power is strongly recomended up to 3,800 rpm. Avoid the use of cruise
control so that you naturally fluctuate the power with your foot."
I'd wager that, if one naturally fluctuated the power CONSTANTLY, or nearly so, revving up to 3800 rpm, then backing-off to 2500 or 3000, and then revving again, one would speed the "wearing-in" process immensely. Instead of driving this way for 1000 miles, it might only take a few hundred miles.
Now, unless someone is willing to buy me a new TDI so I can test this theory, perhaps one of those who are about to take delivery can test it instead. Let's say for 250 miles. You can do it in about 4 hours or so, on the first day. Face it, you want to go for a drive anyway. So instead of varying your speeds between 60 and 70 on a freeway, pick some secondary roads where you can run in 3rd or 4 gears, running it up to 3800, backing off to 3000 or below, then revving again. Revving and backing off, revving and backing off.
Actually this might even be helpful if someone buys a used TDI, that might have been babied by the previous owner.
Edit: I just noticed that Greg Landuyt had recommended something like this for the first 50 miles, for all cars. I think our TDIs might take a little longer.