I had an odd occurrence today where I felt more comfortable aiming at a human head than the 3x5 card. Even though the 3x5 card is more 'defined', I found the nebulousness of a blue head easier to focus on the eyes/nose area and I 'felt' more comfortable shooting at anatomy.
Here's what I shot at:
The card I used to cover the holes afterward. As you can see I have a flier up above from pulling the trigger too early, but other than that, I found I was grouping better on this type of target.
Anyone else experience this?