I've noticed this in using Revit but wasn't aware of a solution until I read through the Bonus CD that Jim Balding passed out at AU.
If you want to print just part of a view you can go to Print... and select Visible portion of current window. The problem is that Revit doesn't usually crop the view exactly as you see it in Revit (if your project window is maximized). To crop prints more accuarately go to Window... Cascade. Now stretch your project window to the shape you want it and print visible portion of current view. Revit should crop the view more accurately. Don't forget to consider paper size and orientation.