I would strongly recommend you use free 1/2 to 1/4 squats if you are using the training protocol in the Free Ride plan to improve your steep skiing. Here is why:
We are using these sets of 50 reps of 1/4 to 1/2 squats to build muscular endurance for skiing down steep slopes, right? Using the principle of specificity, which trumps all other factors in training, we should choose a semi sport-specific movement that mimics the demands of the event we are training for, right? Hence the 1/4 to 1/2 squat choice in this program. It allows us to simulate much of the same range of motion, balance and coordination of neuromuscular firing patterns demanded in the event but in an “overloaded” manner.
Using a guided squatting movement takes away much of the balance and coordination aspects we are trying to target. With the weights we recommend for this program of around 30% of 1RM you should not need a spotter. So, the guided rack becomes a crutch not an aid.
The deadlift is a great exercise and for building strength I would recommend it over the squat normally IF that was our goal I completely agree with Ryan F. on the use of the DL for building maximum strength. This is how/why he uses the DL for his athletes. Very high weight/very low reps. Does that sound like a training recipe for increasing muscular endurance? Not at all. But, it is exactly the perfect recipe for building maximal strength that can then be converted into sport specific power, which is why he uses it.
HOWEVER we are not trying to increase strength in this program. We want to improve sport specific muscular endurance. The dead lift is not as sport specific as the squat in this case nor does it lend itself to the ME training we are targeting as well as the squat.