I'm sorry to hear that Jamey Thompson has left. I think it was a good fit for both he and the Regiment.
I think one of their big issues, well two issues actually are staff retention, and, sorry to say, knowing how to write for white uniforms.
When a corps is constantly in transition (i.e. new drill writer every few years) there is a learning curve time where the drill-writer and the corps become comfortable with each other. I think one of the big reasons the Cavaliers are successful is the staff retention over the years. Michael Gaines and Jay Murphy have been with their respective corps for a good long time. The Cadets have switched writers over the years, but they seem to be with people that have worked with the corps previously, so the learning curve is minimized.
The white uniforms are classic Phantom, but it takes special writing to keep the corps from looking "blob-like" when they move. No matter how well they execute, if it is not written properly, it will look "clumpy." You have to use the whole field and not limit yourself with props everywhere. For me, this year, that was a problem.