Think this is one of many items that could probably use a little clarity in the rules. You have to remember the premise for a lot of these rule tid-bits was along the lines of owners using something like cast-blast paint as a finish. It has only been in the past 5-10 years that the judging in MCA has gotten better at calling out correct finishes. Before I stepped down last year, we were working to require all correct finishes in the concours trailered classes and the intent was to go back through the rules and call out the correct finish anywhere that 'natural' was written. Not sure what will become of all that now, maybe Jeff has more insight?