the casual quilter

A little tip that I was give to make my stippling more uniform in size across the quilt is to imagine a coin about the size of the stipple and to try to make the bulgy part of the stipple the size of the coin. It gets to be automatic after a while. And be patient with yourself. It does take time to get the hang of it.

Holice

I don't understand the recommendation and need to dial stitch length to 0 and width to 0 when feed dogs are down.
Can somone explain this to me.
Feed dogs control the stitch length and when they are down they don't have any effect on the stitch.