1) 310x4=1240 mp + 80x4=320 fuel + 10x4=40 cap vs 640 mp + 260 fuel + 19 cap =
2) Four T-34-76 try swarming Tiger (or whatever) usually get stuck in each other
Use 2 as main line tanks and 2 that flank for rear armor
1)You can see that the fuel of t34 is only 25 % more than fuel of tiger while mp cost is almost double as cost of tiger.
And thats the problem i pointed , they can fuel effectively trade with axis tanks (cause he will loose that tiger and you will lose 2-4 t34 /76 if there were some paks nearby , but that mp cost...)
One tiger less - 230 fuel
3 t34/76 less - 240 fuel (thats not bad for faction that have better map control [in 1 vs 1 often soviets have upper hand in early - mid game])
Also keep in mind that tiger comes after 230 fuel , while t 34 come after 80 fuel than after 80 fuel so you can 2 of them before tiger comes to gain mapcontrol , close harrasment play etc.
But then we dont compare in vacuum.
As i pointed , the problem is not its lethality or survivability . The problem is hight MP teching cost and t34/76 hight mp cost