Sorry have been busy and not on here in awhile.
About hamstring tension -- I think interpretation of what is happening beyond what is visually obvious is an important goal of MA, although my comment may have been a little unclear since there would almost always be some hamstring tension. I do think it's important to mention specifically -- around :06 (viewing the end of the right turn) the feet are ahead of hips prior to transition and after release the feet recenter back (almost) underneath the CM with the knee joint closing, the hip opening and the ankle closing. For this to happen in this particular turn there must be enough hamstring (and glute) tension through the end of the turn to bring the skis back under the skier and recenter. More specifically,both the quad and hamstring are contracted at turn completion, but subsequent relaxation or lengthening of the quad muscle allows the hamstring tension to win out - resulting in the the knee joint closing while the ankle closes, while the hip opens up (due to glute contracting). Also simply looking at the joints opening/closing isn't enough to determine what active muscular movement is involved. As an extreme example, you might see the knee and ankle joint close as the hips open if the skier ran into a tree stump. So I also look at the CM/torso path. Here the torso deflects quite a bit as the knee joint closes, indicating to me that these joint angles are not created simply through momentum and relaxation. By the way, I view the ankle closing as a passive closing of the ankle caused by muscle actions higher up rather than through 'dorsiflexion' (which to me seems to imply an active pulling up of the toes towards the tibia),
Cues for release using flexion - outside leg length decreasing after apex, (knee closing is the primary cue) - also increasing snow spray from inside ski as force transfers to the new outside/old inside ski. No exaggerated upward movement of torso at release.
There is hip angulation with increasing knee angulation towards the end of the turn. The effect on the turn of hip angulation is to create balance by decreasing the 'platform angle' . To be honest I'm not a fan of the skills concept idea that edge angles are a combination of inclination and angulation -- although skiers often use knee angulation to some degree to control edge angles, edge angles are not generally controllable from the hip in my view. Also to say 'inclination' creates edge angles is not very helpful. How is the inclination created? Here you could say edge angles are created in large part through the leg flex, combined with inside leg movement that allows the path of the torso to track inside of the skis (thus creating 'inclination'). Turn completion is also important to set these angles up.
As for maximum angles -- edge angle is highest near turn completion due in large part to slope angle as active edging/tipping near the end of the turn isn't evident in every turn. The visual cues for this are complex, but would involve the degree of knee angulation at the end of the turn, the angle of the skis across the fall line at turn finish, and the actual edge angle achieved.