Hi Jack,
      I think there is a problem with the 
progression in the mystery dance. The partner 
swing is on the ladies side, so B2 leaves people 
on the wrong side. Using a B2: Gents Allemand Left 
1 1/2, Neighbor swing would fix it, but the dance 
still is a mystery.
      A few dances that have a progression at A1 
and then the same A2 and B1 are:
Hey in the Barn		Chart Guthrie 		Improper
A1	Neighbor Balance and Swing				
B2	Ladies Chain, 1/2 Hey		
Pinewoods Crossing		Jim Kitch, et al 		Improper
A1	Neighbor Gypsy 1 1/2, Circle Left					
B2	Circle Left 3/4 Ladies Roll Away (L to R, on 
side) Pass Through Across, Cross Trails* Pass your 
partner by the right, pass neighbor by left		
Pride of Charlottesville		Seth Tepfer 		Improper
A1	Neighbor Seesaw (Left shoulder DSD) Neighbor 
Allemand Left 1 1/2				
B2	Gents Allemand Left 1 1/2 Neighbor Allemand 
Right 1 3/4		
Southern Swing		Steve Zakon-Anderson 		Improper
A1	(new) Neighbor Balance and Swing				
B2	Ladies Allemand Right, Pass Partner by Left 
Gents pass by Right, Neighbor Allemand Left 1 1/4			
Cheers, Bill