Yeah, I also never maintained one speed...ie driving down a 100km/h freeway i'd do 90, then 95, then 100, then 105 (no i wasn't speeding, it just appears that way), up to 110, back to 90, etc...
Never let it idle for too long, basically drove it without boost but did load it up in high gears but not all the time. Seems to have worked for me.