No one in the physics community did take the creation of a black hole serious not even as a nightmare scenario. (First you have to create it, which requires large extra dimensions or a similar deformation of gravity at short scales, then it should not just evaporate immediately, which appears^1 to involve a breakdown of quantum field theories close to a black hole. Then there are additional arguments, but we already assumed that we do neither understand gravity nor quantum theory at the TeV scale, so all bets are off. We may as well assume that the LHC wakes Cthulhu.)
By contrast, the nightmare scenario here is really the worst kind scenario under the assumption that we have a good idea about physics at the TeV scale. We do not learn anything, and even worse the LHC is the wrong machine. With a light Higgs and no additional particles, a slight upgrade to the LEP, the predecessor of the LHC, would have found the Higgs in 2005 and would be a much better machine to study it in detail.
^1 Hawking radiation (and its close relative Unruh radiation) are basically the only two effects which involve both gravity and quantum field theory anybody has any kind of believe in.
Not necessarily. The (design) collision energy of the SSC was 40 TeV, about 3x the LHC's. So it is still conceivable that it could have found something genuinely new which is out of the LHC's reach. I guess Lisa Randall is getting really worried now [1].
Good and useful work has come out of the LHC, enough to make it more than worthwhile. It's just that some of the big hopes don't seem to have panned out.
By contrast, the nightmare scenario here is really the worst kind scenario under the assumption that we have a good idea about physics at the TeV scale. We do not learn anything, and even worse the LHC is the wrong machine. With a light Higgs and no additional particles, a slight upgrade to the LEP, the predecessor of the LHC, would have found the Higgs in 2005 and would be a much better machine to study it in detail.
^1 Hawking radiation (and its close relative Unruh radiation) are basically the only two effects which involve both gravity and quantum field theory anybody has any kind of believe in.