Instead of using restrainers, I have used Brovira and printed it with my standard LPD (replenished) chemistry. Whatever fog is there in the paper I have bleached back with dilute pot ferri. Refix and wash.
It helped me, because I don't have any benzotriazole handy, but I have plenty of bleach.
Thomas, just wondered how the pot ferri differentiates between fog and normal tonal values?