Nearfield is REALLY close, I would call 8 feet or further a relatively normal position. I can listen to my current system from 18 feet away to 4 feet away with pinpoint imaging at the 4 foot position, realism like you are up against the stage. The proper design speaker, with great coherency, can do this and I own several that will, including some pretty gigantic speakers that will play 125db. This 4 foot position is possible with the speakers 12 feet apart center to center. The key is a very coherent signal from upstream components, as well as really well designed speakers. Toe in will have to be adjusted for close distances.
As for Harbeths wearing off, I should qualify this statement: Anyone attending regular concerts and wanting a very true rendition of the instruments at home can find the sound getting old after a while. The true bite of a trumpet, the tougher complex harmonics of a muted trumpet, saxes from sop to baritone, the differentiation of different cymbals and high hat, sizzle of the high hat, these sounds are rounded by Harbeths and they are certainly not alone in that regard. It's a stylized sound. It can be very pleasant. It's what I call a little impressionistic. Nothing wrong with impressionism, but don't tell me a Money Water Lilly drawing is an exact reproduction of the look of water lillies....and the Harbeths are a bit impressionistic.
With many brands and models of associated equipment that are a bit harsh or rough, this "bridging over" of transients is a plus. Unfortunately, such band-aid mixing and matching true detail suffers at each piece of equipment in the chain. With the best, most neutral sources and equipment, it's not needed (the softness), and it will just cover over true musical detail.