Helo CVW guy here, so take my word for what it's worth, but the problem with Super Hornets tanking are stated somewhat well in that article:
1. You're wearing the hell out of the Rhino airframe and putting a lot of extra hours on it than was originally thought of when the F/A-18 E/F program was first being procured. Think of all the extra landings it's doing now and the stress on the wings from carrying all those fuel pods too.
2. When you have one tanking, it's not being used in its fighter / attack role, which reduces the number of aircraft available to perform the fighter / attack roles from the Carrier.
3. These problems are only amplified by the fact that the F/A-18 fleet isn't particularly healthy today.