DD also had a terrible time with the jump rope! She's better now, she can do it, it's just not real pretty. I haven't seen her do it lately, will check and report back.

The swimming thing. Both girls had the once a week for 1/2 hour swimming lesson deal. They didn't learn a darn thing.
I would guess the reason she was successful with swimming this time is because she did it EVERY day and the coaches were great.
They were high school and college students who were on their respective school's teams. They didn't worry like a mom would. They just put the kids through the motions and it never occured to them that any of the kids wouldn't learn how to swim. There is something to be said for that. I really think the intense repetition was what was instrumental. Summer is good!
Maybe you could try a situation like this next summer. Many places offer winter swim team. I'm pretty sure a lot of YMCA programs offer it.