After reviewing the three objects in the title I will argue that they are closely related. In more details: study of effective string theory has lead us to consider 2D quantum field theories with a novel UV asymptotic behavior, dubbed asymptotic fragility. This UV behavior can be introduced by certain gravitational dressing of scattering amplitudes in two dimensions. Gravitational dressing turns out to be equivalent to the T\barT deformation of the initial quantum field theory when compactified on a circle. The same dressed S-matrix is also obtained in a flat space limit of the near-AdS_2 holography based on Jackiw-Teitelboim gravity. In order to preserve the flat space unitarity, however, the conventional Schwarzian dressing of boundary correlators needs to be slightly extended. As an intermediate result I will present a new simple expression for flat space amplitudes of massive particles in terms of correlators of holographic CFT’s.