If that were true Fuzz would have blown up his room up by now, with that 300lb, dual LMS5400 monster he built.
My point exactly
I feel as though many seem to think that just because a speaker or subwoofer is capable of 120+db's (or what have you) that when they hook it up it will just play that loud on its own and there's nothing they can do about it. The reason for wanting a speaker or subwoofer that can play that loudly without going into thermal compression or distorting horribly is 1) if you enjoy deafness or 2) enjoy Reference quality playback/listen to music/watch movies with a large dynamic range. If not than good for you, since it will save you a lot of money
Once properly leveled, a system no matter what its capabilities, will only play as loud as you allow it to. Which is why many preach that you can never have enough speaker/subwoofer, only too little.
If I fed the dual LMS Monster 6000 watts, it would probably blow my front door off the hinges, and by all means it can play much much much louder than I ever care to try even with only 800+ watts/driver. Remember, whatever you hope to get out of sub/speaker, it must be
capable of much more in order to do what you want it to without any hint of strain or misbehavior.