This paper is exactly what I've been thinking about. If I understand correctly, you are using a simple 6db first order crossover and also compensating for the horn’s non-linearity. As you pointed out, there are driver interaction problems with this much overlap, but I still think there is a lot of potential with this type of system. I think is should be very easy to drive and sound good.I have printed this paper and after I go over it in depth, I will get back to you.
Thanks for the excellent analysis!