It seems the recording guitarist can enjoy the beauty of reverb in his head-set, while the recording engineer can afford a track dry and a track wet. Courtesey to the musician would indicate that his best meant licks are really only sincere when faithfully setting up the same sonorus field that he experienced at take time. In other words, if he is enraptured in hazy waves of his fingerings washing through some luxurious reverb as he lays it down, then he hears the same fingerings bone dry - he's sayin "Hey! Wheres the Soar? I want my damn feminin energy crystally twinkles back! You think that whole note bend, though expertly executed, is gonna fly without the sonic gas that is lighter than heaven? You better buy a vowel and get off my knobs!"
Meanwhile some big wig either at the studio or among the entourage simply would not consider recording wet instead of dry. What ever reasons he has, we do want him to be happy. So we split the signal. Just think in terms of "You go your way, and I'll go mine." This will often be practical, and even more often in the coming times as tech advances obscure the separation of artist and medium. In today's world, I know some guys are saying "You can't split my signal! I must deliver the Stuff That Gods Live from this guitar into that box and you better not be around when I do." Good for them if they are so tuned in that they can't bear the malformation of their gear-tryst. These guys may be more common than I figure. At any rate, splitting the signal will have some measurable effect. It may have an audible effect. The technology is available to... Who gives a curse anyway. Excuse me please. ...technology is available to quietly slip our differences under the covers (that's code talk for under the border fences), and may the best man win!