Great conversation, here is how I do feathers.
Mark my spine, starting at the top and stitch my spine to the start of the feather. I feather the left side first using the bump method then travel (very slowly) back down the spine and feather the right side.
There is no right or wrong way to do feathers, it is what is comfortably to you
https://www.youtube.com/watch?v=wKlMTl4XwSY
I hope this link works but if not watch Patsy Thompson on youtube, she makes it look so easy