There is absolutely no sound scientific basis for this! Yes if all the muscle fibres are as fully contracted as possible then it is logical the muscle must be at it's shortest possible length. But there is no reason to conclude that a muscle fibre is best stimulated to grow in a fully contracted state! Or that holding a heavy weight in a position of "max contaction" insures all fibres will automatically be fully contracted whatever the advantages and disadvantages of this might be!Also bearing in mind that many of his trained subjects are routinely using 1000s of pounds in such training and are still far from impressively built I wonder just where you would find a pec dec with 10000lbs resistance to actually capitalise on this theory and achieve a bodybuilders physique even if it were theoretically sound.