By the time the tank hall is built won't the T70 be obsolete and no use ? The German will probaby have tanks out by then and Panzer 4 vs T70 is a no brainer. I'm guessing T90 is the equivalent for the Ostwind.
[CoH:EF-Dev]Walki: BULLSHIT[CoH:EF-Dev]Walki: I'll eat a tree if this won't work now[CoH:EF-Dev]Rizz: ok[CoH:EF-Dev]Rizz: I'll hold you to it<10 minutes later>[CoH:EF-Dev]Walki: I think I really gotta eat a tree...[CoH:EF-Dev]Walki: got a decent one?
also in the guide it sais "You can build any one of these buildings at any time, given the resources" meaning you can get the tank hall first for early t-70s