Upgrading 7.1 to 7.3, use 7.2 as a safe step?

[Nerius Landys]

My upgrades were a success.  I upgraded 3 machines:

1.  7.1 -> 7.4
2.  8.0 -> 8.1
3.  7.1 -> 7.3 -> 7.4

I don't use STABLE, but rather e.g. RELENG_7_4