Given what I know about engines in general and turbochargers in particular, I change my oil pretty regularly at 5-6000 miles, regardless of what the oil life indicator reads. The guy who does the labor for me (I take my oil & filter to them to change) tells me each time I visit: "You don't need to come in until your oil life remaining reads 10-15%", "You're wasting money by coming early".
And I tell him each time I visit..."Yes, I know, I just enjoy putting money into your pocket" in other words, just do the work brother. LOL The fact is, right now, I'm 150 miles overdue for a 6,000 mile oil change yet my oil life indicator still reads 48%! Do you know what that means? It means my engine is clean, very clean which means that my TURBO's are going to last and THAT has been my plan all along! Since the turbo's use the same oil as the engine, I believe that it's going to be imperative to keep that shared oil clean since the shafts on the turbos are spinning upwards of 200,000RPM...and yeah, you read that correctly. Just my opinion though...we'll see how it turns out for me in a few more years........as far as the other myths....that's exactly what they are so nothing more need be said because to address fantasies is to lend them credence.
jeff