Cycle breaking in the bounds takes care of singly recursive datatypes, so we don't need to do it again;
the effect of removing the constraint varies on problem to problem, but it tends to be overwhelmingly negative in conjuction with the new datatype sym breaking stuff at high cardinalities
(* ID: $Id$ *)
use_thy "IFOL_examples";
use_thy "FOL_examples";
use_thy "ZF_examples";
use_thy "If";