Photoshop: Feather Mask/Selection Tool (Akin to After Effects) Also, more intuitive feathering of a selection..

It would be really handy to have something like this in Photoshop to manually adjust a selection's feather. https://youtu.be/K8Fd7Kwch2g?t=1m58s If that tool exists, just let me know I'm being silly. Also, having a live view of what your feather looks like outside the selection when you apply the feather would be incredibly useful for those that can't visualize what "X" pixels feather radius looks like on their "Y" pixel document.