A hole in a shutter would cause fog, or pinspots of light, not dark lines. Either something is blocking light from the film or something is scratching the emulsion side, although I can't think of what that might be in a Pentax 6x7. JWatts image looks like an emulsion scratch or abrasion. The marks are similar to clip marks you might see on sheet film done at a lab using a dip and dunk processor. Again I can't think of what might cause this particular case. Now I really want to know!