Why drop should be before training ?
Because of the hard cap on ST. Unlike all other skills it cannot go higher than 10. So when you get (for example) +0.65 from training and -0.05 from regular skill drop the result is still +0.6 that should be added to ST. If pops are calculated first, ST hits the ceiling and after the drop calculation the end training effect can actually be negative (as is the case apparently). It doesn`t make sense... to me at least.
BBB: 2 (S37 S38); Top tier: 7 (S35 S36 S37 S38 S39 S41 S63); Cup: 9 (S25 S35 S36 S37 S38 S39 S40 S41 S61)