And the 2x video, does it only affect the team bonus or the training efficiency as well.
the X2 vid affect only how fast you can catch the 4X10% bonus
So with two vids and two training of 6,75% condition loss each, you can finish early in the morning with that.

there's the subject of bonuses from training and in game use, like any effect of using condition bonus in beginning of game?
players during match time loosing condition.
This affect their performance later. Condition bonus reduce that effect.
So it's a tiny factor.
I use it some times at extra time of a game.

There are many useful threads in tutorials and tactics. You can read them to earn time and sources.