Training with accommodating resistance was popularized by Louie Simmons and the Westside Barbell crew a few years back, and has often been replicated in many strength gyms across the country. I first came across these principles reading Vladimir Zatsiorsky.
Science and Practice of Strength Training, I’m a huge advocate of this with more experienced lifters, but definitely has some gems that can be used for beginners.
One of theories is that every individual is different on the strength curve and to ability to harness that potential is very difficult. So then came the evolution of using chains and bands to accommodate this dilemma.
I often use it for other purposes and usually ended up with the same result.
Here I have Leah who is nearly close to her 3RM in her front squat and has mentally blocked herself from getting past it. I then added the red bands (25lbs of resistance, barely) to her bar to give her somewhat of a spot (more of a placebo effect). As she lowers the band lengthens, and at end range of her squat the band begins to shorten back to its normal dive give the bar some feedback against gravity and closed joint angle. Here it helped more of her mental block more so than actual assistance but the end result a successful lift.