How do you secure your thread when you begin a new one? Specifically, do you or have you ever used a waste knot?
If using 2 threads of non-variegared floss, I loop start. Always.
If not, I will use my version of a waste knot (I weave the thread through the edge of the fabric a couple of times using enough thread to be able to rethread my needle later).
After there is enough coverage on the back of a piece, I will just anchor the thread on the back and stitch from there.