If you are saying that you did the spraying from in front of the front panel, with the knobs removed, I doubt that it would have accomplished anything anyway, in terms of improving control operation. You have to get the spray inside of the control, which usually means spraying it into an opening on the control that can only be accessed from inside. Some controls are fully sealed, in which case effective spraying is not possible, although sometimes just rapidly rotating the control back and forth a number of times can help somewhat.
Regards,
-- Al
Regards,
-- Al