Truthfully, in artistry this kind of skill is commonplace - many old masters would have apprentices who were trained to create works in the style of their master that were indistinguishable from the original. Even Pablo Picasso believed that it was possible for an artist to channel long dead creative talent by studying the works of other masters.
My father adapted this practice when he started out on the path to becoming a fine artist - for instance this page from Scrapbook: a story of art with the Man in The Golden Helmet and The Polish Gentlemen - both re-imaginings of old master oil paintings.
However, somewhere along the line Jack Whyte chose to forge his own original styles and tell his own stories - the result? Today Beltracchi is infamous and Jack Whyte perhaps the greatest undiscovered modern master.
I've often wonder what would come of a collaborative meeting between the two? I imagine something much like the charming British movie Frequencies where the meeting of people with opposing vibratrions causes all sorts of interesting anomalies.