I read Max Contraction Training...
Sheer is no issue if you are truly isometric, but could be an issue when getting into position.
Personally, I thought the approach was rubbish overall...too much detail for a very non-functional result...
That said, if you like it and it works, more power to you.
"...strength is built one recovery day at a time..." -OMP
Best PL total: 1020 - 350/265/405
Current total: 905 - 315/245/345