I guess its just a habit then for me, I still use a sheet of paper (hey it also protects my easel from the metal grain finders!) and if using my Peak 1, I just leave the blue filter in, constantly keeping it in the open position collects dust, and closing and opening it to often shifts the focus at the eye piece.

Also, for the OP, you do not focus with the red filter do you? no one has brought up that point, but I have heard people doing this in their darkroom work flow. I don't know why they would, but some people seem to do it.