My, 4-year-old 10-pounder has been through quite a few agility classes, and he's doing quite well. We still haven't competed for real, but we're real close to being able to.
Yes, they do lower the jumps. It's generally no higher than the dog is tall, but Yorkies fall in the 8" jump height here in the states. That's a very reasonable height for a little dog. I know a 4-pounder who clears that height easily.
How old is your girl? My instructors encourage you not to do jumps or any of the more stressful exercises (A frame, teeter) until they are a year old. Their bones are still growing.
Eddie is doing really well. He's always among the first in the class to figure stuff out. His big problem now is he doesn't like the banging of the teeter and will frequently try to skip that exercise. But he had a perfect run through last week, so I'm hopeful he'll master it soon.
Good luck, and be sure to let us know how it goes.
Here's a couple vids, first doing a backyard agility course, then struggling at a real course.
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Mike ~ Doting Dad to Jillie, Harper, Molly, Cooper, Eddie (RIP), Lucy (RIP), Rusty (RIP) and Jack (RIP).
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