Jim gave you an answer and I'm nowhere near as qualified to match it
But since you asked here ya go
You can only do so much on the main movements.If let's say you bench at 85 % the optimal amount of lifts are 10-20
If getting your triceps stronger why after that not directly addressing them?What does that have to do with ''mastering the lifts''?
Also I think mastering lifts such as the bench and the squat takes way more than 12 weeks
Just my 2 cents