a theory is not science---it is predictively empty---unless there is possible some future observation which it could not accept a specific measurement which, if it turned out against it, would refute the theory It looks like Distler may have come through. http://arxiv.org/abs/hep-ph/0604255 Falsifying String Theory Through WW Scattering Jacques Distler, Benjamin Grinstein, Ira Z. Rothstein 4 pages, 2 figures "We show that the coefficients of operators in the electroweak chiral Lagrangian can be bounded if the underlying theory obeys the usual assumptions of Lorentz invariance, analyticity and unitarity for all scales. Violations of these bounds can be explained by either the existence of new physics below the naive cut-off of the the effective theory, or by the breakdown of one of these assumptions in the short distance theory. If no light resonances are found, then a measured violation of the bound would falsify string theory." On the surface of it, this seems to offer a TEST! I hope this is the real thing, and would welcome it warmly in that case. The absence of such a paper is the main thing that Peter Woit has been complaining about. And it is presumably what Feynman was objecting to when he said "String theorists don't make predictions, they make excuses." Now this unsatisfactory situation may be changing. Let's hope.