Well, discoverer of this cheat boost his techs to x/x/10/10 in 1500 with France from minor.
I myself made 11/5/8/8 in 1560 with Muscowy/Russia on last beta.
The method is - make youself large, raise you tech almost to grow a level, then reduce youself by vassals and losing 1-month wars to someone having shields on you territories. It gives you 3 l-ups instead of 1 for your money, then repeat.
(Called Dinamical tech boost (c)Tonio on Russian forum)
Suggestion: Make Size, Religion, Vassal and HRE modifiers damage/boost your investments instead of modifying your tech cost (so you'll have stable (relatively) techcost and your investment is divided by modifier)
I myself made 11/5/8/8 in 1560 with Muscowy/Russia on last beta.
The method is - make youself large, raise you tech almost to grow a level, then reduce youself by vassals and losing 1-month wars to someone having shields on you territories. It gives you 3 l-ups instead of 1 for your money, then repeat.
Suggestion: Make Size, Religion, Vassal and HRE modifiers damage/boost your investments instead of modifying your tech cost (so you'll have stable (relatively) techcost and your investment is divided by modifier)