Thanks for the kind words, fellas, and especially you for sticking up for me, Lin.

SP Tech speakers use 30 year old build designs. That's why they sound so good.T-line and Wave guides are not new,just left behind.. 
Hmmm.... I agree in part, Pat.
The basis for Bob's designs may be 30 years old, but to my knowledge, no one has implemented a waveguide quite as successfully (such good dispersion characteristics, so low a crossover point) as Bob. Additionally, as Bob has pointed out several times, his T-line design is proprietary. Those who think differently can take it up with Bob; all I can say with any assurance is that no other T-line, conventional or subwoofer bass I've ever heard competes with what I hear from Bob's T-line.
IMHO, if it were so easy for every manufacturer to realize the success Bob's reaping from his designs, they'd all be doing it.

thinkin' Bob's gonna have to hire more people soon if not now?? 
Yes, I do.