Really? I didn't know short ventral bettas were called something different. I thought rosetails were HMs whose tails were crimpled up like . . . roses. Ooh, I love learning new things.
Actually, short ventrals on an HM are good. Since they are prone to bloat it helps to have short ventrals so you can see their bellies. I don't think I would know Sherman was bloated until he was huge just because his loong ventrals are always in the way. I look but between his fluttering pelvic fins and his ventrals, I never see the part of his stomach that would bloat.