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The title of this article is misleading. The authors have investigated aresonator but not a tunneling barrier see also Refs.\cite{Winful2} The measuredsuperluminal group velocity and discussed is that studied on a Lorentz-Lorenzoscillator by Sommerfeld and Brillouin a hundred years ago \cite{Brillouin}. Itis similar to the faster than light experiment by Wang et al. based also onanomalous dispersion with a complex refractive index of a resonator  \cite{Wang}.  Tunneling, however, is understood and performed by electromagnetic evanescentmodes or by tunneling solutions of the Schr\"odinger equation, which havepurely imaginary wave numbers. The latter includes a purely imaginaryrefractive index. Signals with purely evanescent frequency components cantravel at a superluminal velocity \cite{NimtzH,Nimtz1}. Inside the barriertunneling proceeds even instantaneously, i.e.by a process described by virtualphotons \cite{Stahlhofen}.

Comment on: Direct space-time observation of pulse tunneling in an electromagnetic band gap, S.Doiron,A.Hache,H.Winful