Let us put in a correct perspective quantum string theory for TOE. Firstly it is important to remark that a full understanding of what is really Quantum Mechanics is far to be completely understood in its foundational aspects ,althougth its huge operational-quantitative success.For instance, even in the usual non relativistic quantum mechanics , certainly the notion of electronic orbitals in N-electron atomic physics appears to be a mathematical suitable approximation for the full N-electron atomic wave function.On the other hand in Quantum Field Theory , this ad-hoc choice of what is free and what is interaction is not so "ad-hoc", at least in the QFT (perturbative) scattering sector: free in and out fields are primary objects producing physically observables free N-particles (lorentz invariant!) wave functions-so perturbation is building around them and carrying with the formalism all notions of renormalizations , dispersions relations etc.. .Now quantum strings : Strings are supossedly observable for us mainly through scattering among its excitations by means of an already fixed sigma-model two-dimensional quantum dynamics taking place in the somewhat ficticious purely two dimensional string parameter space-time, where are operating two scales of interaction : one is entirely ruled by the intrinsic string topological genera and other governed by the extrinsic space-time coupling constant , namely : The Regge Slope parameter. So string theory for TOE is a proposal for pure S-Matrix "Heisenbergnian" on-shell "theory" for all particles scattering in Nature (including gravitons). Now the theory's "granus salis" (points not completely grasped-at least for this reader !): Back ground fields are fixed extrinsic classical field configurations fully determined by the imposition of conformal invariance for any genera (which certainly does not affects the intrinsic 2d UV-theories'behavior,but affects its IR intrinsic behavior as a 2d QFT) and at any order in the Regge Slope coupling (all these conformal invariance phenomena quite specific to Polyakov's action proposal , possibly not for a Nambu-Goto string action reformulation of TOE).And at the same time , they are expected to be Schwinger sources (even quite non linear) for the string excitations and to be functionally differentiated in the string path-integral later .Another point is related to Kaluza-Klein Theories -It appears that quantum geometrical theories appear to be trivial QFT theories when used to describe scattering in space-time extrinsic manifolds of higher dimensionality (lambda four scalar QFT is expected to be trivial for D strictly greater than four!). As a conclusion : at most Strings are useful theoretical labs for a fully understanding of what really is Quantum Mechanics (SchrodingerX HeisenbergXEinsteinXNelson) , if there are no experimental tests for its predictions .By the way,space-time supersymmetry still remains solely as a theoretical lab in Particle Physics, nothing more!.