That, right there, seems to be powerful incentive to me to just disallow SSS races from being used for season-counters in OD classes. If a Class wants to have a couple of shorthanded races, they can put 'em on, themselves.
Or, possibly the SSS could decide to still accept the entry fees, but any OD class that has an SSS race as a season counter in the Class, races on a different course from the rest of the fleet.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"