Whats the best way to practice getting your hips going towards homeplate while keeping our shoulder closed to maximize torque? Is it beneficial to stretch your core muscles and back muscles to aid in this process of hip/shoulder seperation? Do you want your core flexed like a big rubberband like lincecum? IF so how do huge overweight pitchers throw so hard that arent flexiable?

Well you don’t need to have hip/shoulder seperation of 75 degrees like lincecum. The normal degree is about 45 degrees to get good torque do not focus on hip/shoulder seperation or as you call it stretching the core. Instead focus on the cause of it momentum by moving out sideway’s while lifting the leg and of course your own flexibility will tell you how much seperation you get.

Ps a big guy like Joba Chamberlian has insane Hip/shoulder seperation and he is a big guy.

see the post on driving with back leg. it explains it probably more than you want to know

Joba Chamberlain isnt out of shape or overweight, hes not fat he is 6’2" 230
BArtolo Colon - 5’11" 245, short and fat but throws hard, gets descent torque but still