  In this paper we skim the true phenomenological requirements behind the
concept of inflationary squeezing. We argue that all that is required is that
at horizon re-entry the fluctuations form standing waves with the correct
temporal phase (specifically, sine waves). We quantify this requirement and
relate it to the initial conditions fed into the radiation dominated epoch by
whatever phase of the Universe produced the fluctuations. The only relevant
quantity turns out to be the degree of suppression of the momentum, $p$, of the
fluctuations, $y$, which we measure by $\sigma\sim \omega^2 |y|^2/|p|^2$. Even
though $\sigma$ equals the squeezing parameter, $s$, in the case of inflation
and bimetric varying speed of light scenarios, this is not true in general,
specifically in some bouncing Universe models. It is also not necessary to
produce a large $\sigma$ at the end of the primordial phase: it is enough that
$\sigma$ be not too small. This is the case with scenarios based on modified
dispersion relations (MDR) emulating the dispersion relations of
Horava-Lifshitz theory, which produce $\sigma\sim 1$, enough to comply with the
observational requirements. Scenarios based on MDR leading to a slightly red
spectrum are also examined, and shown to satisfy the observational constraints.
