How thick should the front baffle of speakers be?

I have to agree with jsautter with respect to lossy cabinets. It’s an attempt to make the cabinets sounds “add” to the drivers output in a perceived pleasurable manner. My (admittedly) personal preference is a design that minimizes the cabinet’s -specifically the baffle influence on the overall output.

To the OP, how do mere moving pieces of moving paper cause the your pant legs to flap? The answer is it’s a sum total of the amp, speaker membrane, voice coil, magnet, cabinet and room interaction. 

Harbeth owners no doubt like the way their speakers sound, but on the larger models the resonant cabinets impart a sound that isnt on the original recording. All speakers do this, but on the Harbeth models I have heard this flavor is very apparent. So I naturally object to those that think these speakers sound natural as I hear the extra "gravy" as a distinct coloration. Just my take.

Mmmmmmm… g-r-a-v-y. It sounds delicious...

I understood that Harbeth's design goal was to make speakers that do not store the energy radiating from the rear waves of the drivers ( not the same as vibrations from the movement of those drivers). To this end the design is a success. The design would not seem to be as successful with the large woofered 40's.  I would doubt they intended to make their cabinets sing. 

Thinking Nicki Minaj, Taylor Swift ??