I tend to leave it running to warm up for 5-10 minutes in the morning, could be adding fuel to the oil there.
Car is DD, work is 20mi ea way, and lots of short trips too. I use it like a car, and drive it like a 911 is capable of regularly.

I first got one when I bought an older M5 to compare it to the sample prev owner had done 40k earlier, looks great still.
The way I see it, as picky as some P buyers are, a few oil samples may help resale to comfort a nervous buyer, or tell me to trade it in.

 

STOP doing this immediately. Start the car, put on your seat belt, adjust your HVAC, and go.

 

You beat me to it.

Idling the car is the worst thing anyone can do and will lead to fuel dilution, especially on a direct injected engine, which is already prone to fuel dilution.

 

That's considered severe service for any vehicle. I'd recommend shorter drain intervals with those short drives, at most three months. Guaranteed you'll see a difference in the ppm of wear metals per 1000 miles and much lower fuel dilution.

 

Problem is, then I have to wait till I'm half way to work for the oil temp to be where I can make the car sound good
Really need more garage space in heated form, car sits outside now.

Alright, alright, it's not proper start-up and drive away that I'm doing, but seat is warm, oil to temp, windows clear, and with snow tires there's no need to wait for those. Not that I red-line it leaving the house, but it is nice to rip up the tach sooner. I've typically changed the oil in any car I like (most everything I've owned) at 3k miles since I was 16, but I waited until 4,500 this time to see if there was much difference in samples. The fact that I could hear a difference in engine noise after an oil change is not new to me, but made me think it would be nuts for someone to go another 5,500 miles to change that same oil, per spec. Since I put a warranty on it to 120k, I could do the who cares approach to maintenance. Many do this with brand new cars, but I've always driven my cars hard and over-maintained them by other's standards.
So if you guys had to pick one to buy used and had to keep it till 200k:
A: car that had been started-up and driven off right away but owner didn't wait for oil to come to temp before several rips up the tach, in say, 4-7k range, or
B: car that was left to idle too long then driven normal for about 5 minutes before getting whopped on.

 

Neither are good for the engine long term. Keep the rpms down until the oil gets to about 160F then you can get on it. If you never get the oil over 215F for an extended period on a regular basis, short drain intervals are your friend. The factory's recommendations are to reduce total cost of ownership. They want you to buy a new car when the warranty comes up anyways. If you plan on keeping it, what is done now will directly affect the longevity of the engine.