  In a previous paper (hep-th/0304045) it has been argued that tachyonic
Dirac-Born-Infeld (DBI) actions can be obtained from open string theory in a
limit, which generalizes the usual massless DBI limit. In the present note we
review this construction focusing on a key property of the proposed tachyon
effective actions: how they reproduce appropriate Veneziano amplitudes in a
suitably defined kinematical region. Possible extensions and interesting open
problems are briefly discussed.
