I marked this exercise today as easy, the reps and iM don't impede me and I don't find them difficult (though I do still get a little crepitus in one of my knees if I force the depth of my squat). If my form is lacking in one way or another on either the PE or the iM please do let me know, because as of now I'm not sure what else there might be that I can see that should hold me back from PE4. Yes, I recognize the forward lean of the torso and the ankle dorsiflexion on the PE, but those things I feel like would get a lot of attention in PE4 and PE5, no? I could be wrong, it has happened before. Anyways, here it is from three angles.
