Gimmick. Just work your butt off and when something gets easy make it harder...They bring up a lot of "muscle confusion" in their program. Its BS. Basically, if you want to save yourself some money but get the "P90X" workout, do this: Set a number of reps and weight (whichever applies) to a certain exercise. Make it fairly difficult. Once it starts getting easy after many workouts, even a little bit easier, make the exercise more difficult. Increase the weight, the reps, or just take your time with it more. (Lifting weights slowly is a lot harder)
I'm only 16, but I've become a bit of a fitness expert, lol.
"The wise man thinks he knows nothing.
The fool thinks he knows everything."