Sorry, I feel that the thread has gotten snarky and was kind of avoiding it!
I'm disappointed I did the link incorrectly so it's no longer permanent! I really don't know much about the Feathertails othen than they are an extreme form of the Rosetail and that they are difficult to breed because they often are so mutated that they ha e difficulty swimming and other mutations, such as irregular scales and miniature fins! Unfortunately, this is the price bettas have to pay for us to develop new strains.
However, if they can ever get the" kinks" worked out (and remember that all of our bettas are 'unnatural') I think these fish are gorgeous and would love to own a healthy and happy one!
Can you guys see this one?
Notice the extensive rays in the fins (resembling feathers), and also the stinted/small tail fin.
Now looking at this white betta (which looks more like a 'plain' rosetail, because I can't see the feathers) you can see how difficult it looks like it must be for him to swim!