I'm going with the eye test on this one. I think he has a good swing, with good instincts using the whole field. He looks like Betts to me, except he can't field, but he is athletic enough to adapt.
His winter results were a mixed bag. Nice K/W, but walks disappear in the pros. And he had -0- HRs. That could simply be our scouts refining his approach.
But his AAA results were awful. A 19/6 K/W in September with 1 HR?
Good weight is undefined to me. Probably good, but maybe not.
So I see two questions. The first devolved from questioning who would replace Yoshi, if Duran got traded. I don't see any chance Campbell would do the job. We'd probably lose at least 40 OPS points.
Which leads me to my second question. What is KC's best long-term development? If we replaced Yoshi's projected .767 with some 25 year old AAAA .725, I could be talked into it. But IMVHO, Campbell needs a full year of AAA. He was a top-10 prospect less than a year ago. Trying to promote him to replace Yoshi would be irresponsible.