I've been looking on the many hidden commands that are included in the program, but are undocumented. One of them is AECPolygon. One of the uses I thought of would be to hide surface contours with out having to select each polyline, like you would have to do with the boundary hide command. Learn more after the annoying jump...
You can use existing polylines or create the AECPOLYGON the same way you would draw a regular polyline. In this example I will create the AECPOLYGON's from existing polylines. To start type AECPOLYGON into the command line. Select the Convert option and select the PLines option. Select the polygons that you want converted to mask the surface.
If you want to keep the source polylines then select No, otherwise choose Yes. Now you will want to change the style of the newly created AECPOLYGON to do this press S for Style. A style manager will pop up onto the screen. Right click on AEC Polygon Styles and Choose New.Provide a name for the style, I choose HideContour. Go to the other tab and select Use Background Mask and select OK at the bottom of the screen.
To get them to show the correct style, select the AECPOLYGONs and go to properties and change it to show the style you created.
Now when you will have the surface contours will be hidden by the AECPOLYGON.
Unlike the Surface Boundary Hide, you have to worry about draworder and you can't print them from model space without changing the color of the mask (if you do it will come out as a black box). As long as you want the surface printed first it should be pretty easy to manage; send any surfaces to the back in which you don't want the contours being masked, then send the AECPOLYGONs to the back and then the Surface to be masked to the background.
This may also seem like the same as the wipeout command but there are somethings I like which are better, for instance you can add and remove vertexes throught the right click menu and there is an extra grip between vertexes that allows you to drag the edges and they stay parallel to the original line. Give it a try you may like it or not.
Disclaimer: I haven't actually used this in production, but will probably do so in the future.