What is best tweeter height for the Devore O/96?

On the Devore Orangutan O/96 with the supplied stands from Devore Fidelity, the tweeter height is approximately 31.5 inches from the floor.  By comparison the tweeter height on the Devore Gibbon X is much higher at approximately 36 inches from the floor.  As a general rule, I always thought that it was more ideal to have tweeter height at approximately 36 inches, with the goal of having the tweeter at or near ear level, while in a seated listening position.  Why does the O/96 have such a low tweeter height?  What would be the effect of raising the O/96 to elevate the tweeter height to ear level?  John Devore could have made these stands any height he wanted for optimal sound, so why have the tweeter height so low?  Thanks for your comments.