I guess, it depends on what one considers, reasonable. My thinking is that even if she does not do very well at first, she would be doing the course that she will continue doing pretty much for the rest of her life.
Reasonable to me means being able to do most or all of the course properly, with mistakes occurring because of situations beyond your control (sheep, weather, etc.) For example, I personally would not take a dog that's slicing the top of its outrun that badly at 100 yards and expect any better result at 160 yards. In fact, I'd expect things to be worse at a greater distance where you have even less influence. If you spend the winter taking her a buch of different places and have her picking sheep up off a set out person/dog until she's able to do a proper outrun/lift at 160 yards, then that's one thing, but just moving her up because the higher test is the one she'll be doing the rest of her trial career doesn't quite make sense to me, unless the plan is to train for the course instead of training the dog to do practical work that can then translate into success on a trial field. Dogs can become trialwise and they can learn bad habits as easily at a trial as they can at home, and habits learned at a trial can be harder to fix, IME. Whenever there's a problem, you need to move things in closer and fix the issue at hand before expecting it to be sorted out at a distance.
As for the usefulness of class 1, I have some thoughts on that. The ability to "park the sheep near the handler" is quite necessary for setting up a shed. Driving sheep to an unspecified location (i.e., not through a gate) is how I teach driving. I don't have any gates here to practice with. I pick a point on the horizon and drive toward it (the point on the horizon mainly being to enable me to keep a straight line). One time at a novice trial, someone asked judge Kent Kuykendall what the point of wearing was. His response was that the handler's and dog's ability to control sheep *between* them was the start of being able to set up a good shed. Food for thought. Aren't there times at home when you might want to lead the sheep somewhere and have the dog bring them along behind you without running you over? Is testing for that at a trial really impractical? Does wearing actually exclude the ability to cross drive? I don't think so.
Think about the elements of each trial course in terms of how they might translate to work at home. Just this morning I had my dog drive the sheep away to an unspecified location (I didn't even care where, just away). When I was done dumping feed in the feed bunks, I sent the dog around and had her fetch them to the feed. I do that every day when I am feeding sheep either grain or hay. Seems like a very practical task to me. No cross driving needed. And yet, my dog can cross drive and does so in trials. But at home, I don't have a whole lot of need for it, whereas I do have a need for a dog who drives the sheep away and then brings them back when I've cleared myself out of the way.
I'm not trying to convince you one way or the other--it's your choice to do what you think is best. But I also think that the class 1 tasks aren't entirely pointless either and I don't see how they could mess Bonnie up when it comes to practical work. And if trialing is supposed to be a test of elements of practical work, then I don't think the class 1 is going to be the ruination of any dog.
Just my opinion of course.
J.