  Recently, one analog of the Anderson's Theorem for the $s$-wave
superconductor has attracted much interest in the context of the $p$-wave polar
pairing state of superfluid $^3$He in a model aerogel in the limit of strong
uniaxial anisotropy. We discuss to what extent the theorem is satisfied in the
polar phase in real aerogels by examining the normal to polar transition
temperature $T_c$ and the low temperature behavior of the superfluid energy gap
under an anisotropy of a moderate strength and comparing the obtained results
with experimental data. The situation in which the Anderson's theorem clearly
breaks down is also discussed.
