http://anidb.net/perl-bin/animedb.pl?show=rel&aid=409
Other than declaring PS OAV a Mihoshi Special sequel, not bad. I know Hayashi worked on both, but the two don't seem to have anything to do with each other.
The gxp branch should be listed as a sequel or spinoff of ova3, not off the main series. While dual could be linked to the original & gxp. The chart also neglects photon & it's connection to isekai. I can overlook gosenzo/anata dake & agga ruter, since their references tend to be more obscure. Tenchi's anidb chart always annoyed me.