To be fair you dont see De Allende, Danty or Aki doing that too much either.....I find it hard to believe that you just convert a 7 into an IC. The intricacies of defending at IC is very different to a poaching back row. It's a specialist position
Ball in hand should be fine, although I've yet to see Earl whip a 20 m pass out to his wing.
I dont think anyone is saying its just a straight forward switch. Most would prefer to see an actual 12 coming through and really making that position their own (Atkinson, Hartley, Ojomoh etc)....but what people are saying is in an absence of actual 12s with the current trend skills set or even putting their hand up with consistently excellent performances, then Earl is an interesting option.