But I think there may have been varnish or gumming on the plate. I was gonna toss the rest of the bottle in the next tank.
Not sure if I understand this right, but what you said leads me to believe that you think that the fuel injector cleaner will clean up the throttle plate. If so, then I can tell you it will not, all that goes by the throttle plate is filtered air and blow-by from the valve cover vents ( if you don't have a catch-can ).
You have to remove the TB and clean the plate up yourself .....