Typically primary feathers have blood running through them. As feathers get older and its time to drop them they die off and fall out during a molt. Unless you are planning on showing them I wouldn't pull the feathers out. I would wait for them to fall out on their own. If you look closely, they are embedded and grow out of the scales of the foot and leg.
If you have to pull them out, I would cut them short first, a little bit of length at a time. If you reach a point where you cut into the shaft of the feather and it starts to bleed, stop there. That will bleed a lot if you pull that feather.
That is the best advice I can give you. I hope this helps. :) Why on earth would anyone tie out a silkie? The only birds I have ever heard of doing that with are game birds as they will kill each other given the chance.
Let me know what you decided to do okay?
PS I tried to email but it wouldnt let me.