Removing plastic phase plug from tweeters?



I read somewhere that removing the plastic cover from metal tweeters will clean up the treble and make the speakers sound smoother and more natural. But ive also heard that this "phase plug" or whatever its called is there for a reason- to break up any unwanted resonances that may be caused by a metal tweeter.

Has anyone ever done this, and what sort of results did you get? I'm considering doing this to my PSB's but dont want to kill the resale and possibly make the speakers sound worse.
dave123456
quote from site-

"• Remove your speaker's cloth or foam grill. Snip off any plastic phase ring in front of the tweeter. You'll hear as much as a 100% improvement in treble."
I wonder why they don't manufacture the products instead of selling them since they have more expertise? Do they replace the tweeters if they turn out worse?
They also advise you to listen by sitting on the floor five feet away from the speakers. Pierre Sprey has some unique ideas about audio.
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At Zero Dark 30 (That's real late at nite, for those in Peoria) I will sit right in front of my Maggies. Sound is spectacular, full range, with an amazing wrap around effect. Almost like the ultimate 'open air' head phones.
As for those who modify tweeters? Best of luck!