* far in the future:
* If \c i is the index of the last frame such that all frames from
* 0, ..., \c i have been finished, then \p header().index() should be
- * at most \c 2*parallelizationFactor-1 larger than \c i, where
+ * at most \c parallelizationFactor larger than \c i, where
* parallelizationFactor is the parallelization factor passed to
* setParallelOptions().
* Throws APIError if this constraint is violated.