Here's a read that can help people understand the relationship between installation, cross-over points, and stage height.
The first question that needs to be asked...how do we localize objects vertically? Now here's a link. It doesn't answer the question I just asked but brings out a lot of different variables that coincide with my question.
Buwalda Hybrids International Bulletin Board • View topic - My views on tweeters and crossovers