X-Plane has pilots on the team, but none of them fly many tail draggers. In general, Austin uses his experience to tweak the flight model. If people can provide enough specific information, gathered from very controlled experiments & real life, or from official documentation such as the POH, we will be able to use it to adjust the flight model as well.
The only tail dragger we have in the default fleet is the Stinson, so that would be a good aircraft to do any tests with. Otherwise, you could possibly contact the developers of the third party tail draggers to see if they have noticed issues too. If they have, they should contact us about it directly via the bug reporter.