white thread on black-ish batting? Yes, I did!!!!!
My t-shirt quilt had a blue/black mottled backing. I used black thread in the bobbin. But .. the t-shirts were white, red, blue, and green so I matched the top thread to the shirt. All was well except for the white shirts. The top thread poked through a little bit on the back no matter how I tried to adjust the tension to eliminate it. So .. out came the Sharpie and .. I colored (I made sure the stitch was locked and not just laying on the fabric. All seemed well so ... I colored.) :0