I should clarify...
I do agree with you that greater distance will be better. My suggestion that 3' would be reasonable is not meant to be a suggestion for "Best Practice."
While the Speakers themselves are large, the Drivers are in as close proximity as can be had without modifying anything. Center of the ScanSpeak Woofer to Center of Raal on my Monitors is less than 10". If I were listening in close proximity, I would likely try to sit about -5° from Tweeter axis and have as much space between me and the Speakers as possible, with another 12-18" between the wall and the Speaker if possible. *shrugs I did suggest above that 4.5' would be better than 3'!
Anyway, this is hypothetical on my part. But I do think they can be used successfully this way, especially if one has some room to play with.