The author of the article mentions linear phase - this requires DSP processing with a FIR filter and if you want it to be phase linear from 20 Hz it will mean a latency in your signal of over 200 ms. In a pro-audio situation this is simply not an option. Electronic circuitry and electro-acoustic devices are pretty much always minimum phase.
Personally I think the importance of phase response in low-frequency systems is overrated – I don’t mean to say it’s not real, just that in the real world there are many things that influences our perception of sound. In our speakers we deal with it in crossovers through making sure the acoustic response of each driver conforms to theory and through careful design of the port/resonant system.
In hi-fi there are so many weird explanations related to phase and it can really get crazy when you hear people explain why 6dB/oct filters are “perfect” -unless it is actually done well, like in Dunlavy's.
I will recommend "the loudspeaker cookbook", "the master handbook of acoustics" and "Handbook for Sound Engineers: The New Audio Cyclopedia" by Glen M. Ballou - these books contain a lot of the most important research on electro acoustics as well as psycho-acoustics.
I'm actually not going to say what system is more accurate - it depends on too many things. If both systems are well designed they can both sound excellent, but yes, at least in theory closed box has the upper hand when it comes to group delay and the reproduction of impulses.
Lars T