It's great that Leaf's vet visit went so well!
I don't see any indication that Leaf is part Jenday.... if he is, then there's not much jenday in him!
Sun conures tend to be more orange than jendays, and jendays tend to be more "yellow".... in the head region. Now, there are some jendays with extra facial colors, but general rule of thumb, jendays are more "yellow". It's easy to see when you see both species next to each other, like these images.
http://www.crittersandconservation.com/cnc/uploads/images/conures.jpg
http://images1.americanlisted.com/n...sun-jenday-conure-americanlisted_40946029.jpg
Vs these two jendays that do have more facial coloring than the ones above (could be an age thing, could be genetics)
https://upload.wikimedia.org/wikipe...g/768px-Aratinga_jandaya_and_solstitialis.jpg
As far as harness training goes.... pfft!
Charlie, my mitred conure, was born in 1994. I don't know what month, let alone day, but he is a first generation captive bred parrot. Both of his parents were wild caught imports. His breeder only bred his parents once before giving the pair to a friend.
For the first 10 years of his life, Charlie lived with a man. Then, for about a year, he lived in a pet store. I *hated* dogs though, because whenever a customer brought a dog in, he'd go berserk and start screaming his head off! Which resulted in him having to stay in the back, with the bunnies... (back of the store is larger than the front!) Then, he spent another year in foster care, where he tried to bully a blind ruby macaw and got the short end of the stick. It was in his foster home, when he was around 12 years old, that he first wore a harness.
His first harness was more cockaitel to sun conure sized....
He's since been upgraded to some larger harnesses (I have 2 Feather Tethers and 1 Aviator harness for him)
Dogs don't bother him anymore.
And me mentioning he got the short end of the stick between him and a blind ruby macaw???
Charlie's beak no longer grows properly since he's missing part of his lower beak. This means that he requires beak trims for the rest of his life. This happened when he was 12 years old. He's been with me since October, 2006. Since his beak doesn't grow normally, I have to use a dremel to keep his beak in shape. I even have a little kit full of various dremel attachments for cutting and grinding his beak. (I typically only use 2-3 attachments, though)
Charlie is 23 years old this year. Given a choice, he'd happily remain glued to me!