We study the Lipschitz simplicial volume, which is a metric version of the
simplicial volume. We introduce the piecewise straightening procedure for
singular chains, which allows us to generalize the proportionality principle
and the product inequality to the case of complete Riemannian manifolds of
finite volume with sectional curvature bounded from above. We obtain also yet
another proof of the proportionality principle in the compact case by a direct
approximation of the smearing map.Comment: v2: small changes in the introduction, references and section 2.3
(one minor mistake corrected) v3: corrected sections 2.1, 2.2 v4: new section
2.1 about 'exponential' neighbourhoods, more details about the procedure
itself in section 2.3, barycentric C^1 homology corrected to piecewise C^1 in
section