  Recently, A. V. Boris and colleagues claimed to deduce a decrease of
intraband spectral weight (SW), and a transfer of SW from intraband to
inter-band frequencies, when optimally-doped or slightly underdoped cuprates
become superconducting [A. V. Boris et al., Science 304, p. 708 (2004)]. We
show that, while their data agree with others [H. J. A. Molegraaf et al.,
Science 295, p. 2239 (2002) ; A.F. Santander-Syro et al., Europhys.Lett 62, p.
568 (2003)], their analysis is flawed. They cannot disprove the results which
yield a superconductivity-induced increase of intraband SW, and a transfer of
SW from high to low frequencies, in underdoped or nearly optimally doped
Bi-2212.
