Do we have a tech director?
We don't have that but we can still discuss things you and I
Hmm.. I don't think it is possible to allow some techs only for specific countries. Anyway, I haven't seen that ingame yet.
It's possible and I can tell you how if you wish. What I meant is that if there are 2 alternative paths in terms of research it should be very expensive to leave the current path to follow a new one.
EDIT
Let say, for example, that the tech starts with Early Auftragstaktik and Early Normal tactic respectively and that the cost for those is the following
Early Auftragstaktik - already researched for Germany
centralized_execution 10
small_unit_tactics 10
large_unit_tactics 10
combined_arms_focus 10
decentralized_execution 10 (doubled)
Early Normal tactic - already researched for the others
decentralized_execution 10
small_unit_tactics 10
large_unit_tactics 10
combined_arms_focus 10
centralized_execution 10 (doubled)
In this way, even though the German tech branch is better (I would say, ceteris paribus, should grant about 10%/15% combat bonus), is not convenient for a country to leave its actual path.
Please find below the tech by path
Early Auftragstaktik
Auftragstaktik
Leading by task
Forward control
Combined-arms forces
Cross-branch tactical experience (late years)
Early Normal tactic
Normal tactic
Leading by orders
Centralized control
Separated-arms forces
Specialized-branch tactical experience (late years)