Bruno's Nightmare is in fact a rotating feed in which one juggler moves through the middle of the passing pattern.  In this pattern, one must imagine that each juggler represents one ball in a giant 3-ball cascade.

  
  

The above diagrams show B's movement, passing through the pattern to the other side.  The feeder's position then changes from C to A.  It's the feeder (C in this case) who counts (if there is a need to count) the 6 passes it takes to change positions.  As soon as C makes the sixth pass, it's his turn to begin moving to the other side, passing in 4-count (every other).  A is left as feeder, (switching to 2-count) and counts his first pass at the same time as C's sixth.

During B's movement, A should also move slightly (see figures 2, 3, and 4), otherwise B might get knocked in the head.  

Once you learn this, try Bruno's nightmare in 3-count or turbo with 3.

Rhythms:
4-count (every other) and 2-count (solids) as in a normal feed.

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