  A collection of integer sequences is jointly ergodic if for every ergodic
measure preserving system the multiple ergodic averages, with iterates given by
this collection of sequences, converge in the mean to the product of the
integrals. We give necessary and sufficient conditions for joint ergodicity
that are flexible enough to recover most of the known examples of jointly
ergodic sequences and also allow us to answer some related open problems. An
interesting feature of our arguments is that they avoid deep tools from ergodic
theory that were previously used to establish similar results. Our approach is
primarily based on an ergodic variant of a technique pioneered by Peluse and
Prendiville in order to give quantitative variants for the finitary version of
the polynomial Szemer\'edi theorem.
