As we all know in Adan's timeline in Phantasy Star III his twin sister Gwyn has a tiny glitch that makes her not gain tech levels upon increasing her level. Do you think this is just a bug left in by the programmers, or is it a clever disguise for Gwyn's character?
I believe that since Gwyn is Adan's twin the two are linked as most twins are. Gwyn's technique level doesn't increase is because her bond with her brother is strong and his strength is there to fill in what Gwyn lacks in as well as her techniques are there to fill in what he lacks. Sure you can increase both of their technique levels via the shop but I believe that the two share a certain thing where Gwyns tech levels do not rise due to Adan's strengths. But thats just me