Probably, but I don't think its your fault. Whatrelease of Revit are you using and what build. the current release is 9.1 and the current build is 20060928_2300. This is a newer release than the orignal 9.1 in August.
In my experience the Linework tool does not work on Edit Cut Profile Faces or Boundary between faces, because this is an extension or reductionof an existing building layer in a system element family object.
I forgot to say that anothe way to deal with walls, if walls are what you're trying to use the Edit Cut Profile tool on, specifically extending the top or bottom of wall material layers. Then you may want to unlock the specific wall material layers in the wall type dialog box - edit button for Structure parameter. If walls are not the objective, but relationships of one element to another, then when you create Edit Cut Profile objects the line style assigned is System Family Detail Lines with no Type selection available. I have not found an object style for this so I presume it can not be edited directly. You can go to the Object Styles under the Settings menu and find the Object (ie. floor, roof, etc.) and reset the line weight, color, pattern in cut or projection. This directly affects the line weight, color or pattern for the edit cut profile to that element object. Then you can use the linework tool on the normal lines of the element object to override the object style settings. Unfortunately this is a category wide change to all similar elements.
I was trying to use the tool on the roof, in the case of a notched rafter, and your advice about changing the line weight of the cuts for the roof was helpful. Thanks. Of course if I turn the lineweight of the roof cuts down, I don't think this will be a bad thing, since multiple cuts through layers of building materials would still yield a dark cut line.