How to put multiple visual elements into a single link in a urdf?

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I know above a certain complexity it is better to move entirely to collada meshes, but I think it would be nice (and preserve the ability to place and scale visual elements within a xacro/urdf) to be able to have multiple visuals within a link like the following, which would create a composite object out of a cube and a cylinder mesh (or a cube primitive or anything else):

 <link name="link1">

 <visual name="vis1">
     <origin xyz="0 0 0" rpy="0 0 0" />
     <geometry>
       <mesh filename="package://testbot_description/meshes/cud.dae" />
     </geometry>
 </visual>
 <visual name="vis2">
     <origin xyz="0 1.0 0" rpy="0 0 0" />
     <geometry>
       <mesh filename="package://testbot_description/meshes/cylinder.dae" />
     </geometry>
 </visual>  
 </link>

Right now I'm creating extra fixed joints and links that are purely for visual purposes, it seems like they pollute the xacro and rviz environments. Is there another way to solve this?