Uka,
I have run into this problem many times, especially when drafting cast parts with the fillets shown. A non-shaded view (HLR) has the option of either being shown with tangent edges, tangent edges removed, or shown with font. Often the drawing looks terrible in any of these display options. This is a big weakness IMO because I often have to go around hiding or showing edges depending on the display mode to get the look I want for the drawing. Often this is very time consuming for detailed and intricate castings, especially when issues like the one you are describing pop-up. Sometimes I give up and just elect to show the view in its shaded mode. I actually submitted an enhancement request to have a hide/show edges tool (similar to the current hide/show annotations tool) because it would save the time of having to right click and select "Hide Edge" for each edge you want to hide. I have found what works when an edge isn't hiding correctly is to make the view a wireframe, and then select the edge you want to hide, and then hide it. Then switch back to HLR and the line edge should then be hidden correctly. I spoke to my reseller about a year ago concerning this apparent bug and it was submitted, but I haven't heard anything yet. My reseller confirmed they saw the same thing when I sent my drawings and models to them. Hope this method works for you. I wish SolidWorks would focus on the drafting environment more in the next few releases. I view the drafting environment as having some weaknesses that if improved upon would sit very well with the SolidWorks community. There are still an awful lot of us out here that would never consider going without drawings for at least the forseaable future. They are a way of documenting design intent (tolerances, finishes, notes, etc...) that can't really be captured in a solid model that gets sent to a cam package, inspection package, or whatever automated solid-dependent system.