Hi Jon,
We use this all the time as well - you cannot discharge it as it will basically turn to water - but you can add a discharge underbase if you feel the print needs it. Usually it does not though this binder covers really well and if it is left silver rarely needs to be based.
If you tint it gold it will sometime come out better with a base though to keep the gold from looking too green on some black garments, but again this ink will not discharge and won't work properly if you try to actually discharge it.
Hope this helps.
Thanks,
Dave