Albert, your response mirrors the findings of someone else that i know that tried Deflex. He put Deflex inside of a full range floor standing cabinet and thought it sounded WORSE than with the factory installed damping material. After much experimentation, he found that removing almost ALL of the Deflex panels that he installed gave better results.
My conclusions on his experience is that the box was obviously contributing sound almost as much as the drivers were. While he might have minimized the resonances of the box to a point, he didn't like the sound WITHOUT the contribution of the box. In other words, it is / was strictly a matter of "personal taste".
Something else to consider is that the amount of internal stuffing and its' placement might have a LOT to do with the "voicing" that the original designer was trying to achieve. Altering this might alter the speakers' sound and performance to something completely different due to apparent box volume that the driver sees.
If your going to "mess around" with stuff like that, try to make detailed notes of where, how much, loose or tightly packed, etc... damping material is at from the factory. This way you can always back-peddle if need be. Never "assume" that a "modification" will result in "better performance" unless you've done it before in a very similar situation. Sean