The following constraints show a stringency relationship -- not necessarily a logical one, but in the data given.

*New Pi	 has a strict subset of the violations of 	Ident(+B to -B)
Ident(+ to -) in RNU	 has a strict subset of the violations of 	Ident(+B to -B)
*i u in RNU	 has a strict subset of the violations of 	*i u
*i u	 has a strict subset of the violations of 	Agree(back) in high
*i u in RNU	 has a strict subset of the violations of 	Agree(back) in high

