All Relic needs to do is switch the units around the tiers then make slight balancing adjustments. Relic did move units around Tiers before, do you remember that the Elefant and the Tiger used to be in T4 buildings? and the Panzerwerfer used to be T3? The past shows that they are able to make the adjustments.
The Soviet Faction is unfinished and Relic completely abandoned them either because they don't know what to do with it, or they are completely satisfied with the faction ( which they shouldn't be)hence I am giving them ideas to improve and fix the faction.
So simple!
All relic has to do is something that they will never do!
Also, that was back in the beta, before the release, you know, betas are exactly made for that.
Never tier switching happened after release.
Stop deluding yourself that any tier or doctrine changes will happen, they won't, relic have stated that enough already.