Mapfile / Layer / Group / Name confusion

[Chip Hankley]

I'm confused about how NAME and GROUP work when defining layers in a
mapfile. In the snippet below, I have two images. One has been resampled
for low resolution viewing, and one for high. I'm using MINSCALE and
MAXSCALE to control when one draws... at any scale, only ONE image will
draw. I want this to be transparent to the user, and I only want ONE
entry to show up in the legend. However, two entries show up (I'm using
dBox... so that could be part of the problem). What am I missing?
 
  WEB
    IMAGEPATH "C:\Inetpub\wwwroot\tmp\"
    IMAGEURL "/tmp/"
    MINSCALE 10
    MAXSCALE 2800000
 
    METADATA
      # dLegend XML legend control
      dlegend_metagroups "background"
 
      dlegend_background_name "Background Layers:"
      dlegend_background_layers_and_groups "Aerial"
      dlegend_background_element "radio"
 
      dlegend_Aerial_name "Aerial Photograph"
    END 
  END # Web Interface Options 
 
  LAYER
    NAME "Aerial_HR"
    GROUP "Aerial"
    TYPE RASTER
 TILEINDEX "HR_index"
    STATUS DEFAULT
    CLASS
      NAME 'Digital Orthophoto'
      KEYIMAGE graphics/doq_keyimage.png
    END
    MAXSCALE 10000
    PROCESSING "COLOR_MATCH_THRESHOLD=3"
  END
 
  LAYER
    NAME "Aerial_LR"
    GROUP "Aerial"
    TYPE RASTER
 TILEINDEX "LR_index"
    STATUS DEFAULT
    CLASS
      NAME 'Digital Orthophoto'
      KEYIMAGE graphics/doq_keyimage.png
    END
    MINSCALE 10000
    PROCESSING "COLOR_MATCH_THRESHOLD=3"
  END

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