To regenerate them for every step, extend AbstractMoveFactory directly, instead of CachedMoveFactory. isMoveDoable() should only be used if it corrupts the solution. Generally, it's not a good idea to use it to check hard-constraints (even build-in hard-constraints). Check the manual for the difference on "build-in hard constraints" and (normal, real) "hard constraints". The accepted move size is the number of moves that are accepted, not the number that is selected. This is the work flow: - x moves get selected. The MoveFactory - a non doable move gets ignored. y moves are doable - the move's score is calculated - the move is accepted or not. z moves are accepted - the best move is selected as a step. With mininimalAcceptedSelection, z is limited. Op 13-07-12 17:54, Garf schreef: -- With kind regards, Geoffrey De Smet