I bumped this latte art attempt before the photo was taken. It was better. Really, it was. 
Just like my previous latte art post, this was a 2nd pour of the frothed milk. I wonder what is going on there? The first pour should be the better one.
Perhaps more experimentation is needed?
Cooler, bubble-free milk seems to produce better results per this guide (Step 5: http://www.coffeeresearch.org/espresso/milktexture.htm).
That site is by one of the INeedCoffee contributors, Michael Griffin.
By the time I did the 2nd pour, the milk was below 150 degrees and more importantly – I had not swirled it – so it had lost most of its micro-bubbles. A few minutes had elapsed.
I’ve read every tutorial and watched every video on latte art there is. The best tip is to just keep practicing, which is tough for someone that only drinks straight espresso.
Every..? Ok, you know better than to make a statement like that to me, MAS
I agree with Rachel, a designed experiment under controlled conditions in your brewing location may be the answer and you can even have latte artists with different skill levels as one of the factors.